agora inbox for [email protected]  

help / color / mirror / Atom feed

[PATCH v33 01/11] Add a syntax to create Incrementally Maintainable Materialized Views
2648+ messages / 2 participants
[nested] [flat]

* [PATCH v33 01/11] Add a syntax to create Incrementally Maintainable Materialized Views
@ 2019-12-20 01:05  Yugo Nagata <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

From: Yugo Nagata @ 2019-12-20 01:05 UTC (permalink / raw)

Allow to create Incrementally Maintainable Materialized View (IMMV)
by using INCREMENTAL option in CREATE MATERIALIZED VIEW command
as follow:

     CREATE [INCREMANTAL] MATERIALIZED VIEW xxxxx AS SELECT ....;
---
 src/backend/parser/gram.y     | 32 +++++++++++++++++++++-----------
 src/include/nodes/primnodes.h |  1 +
 src/include/parser/kwlist.h   |  1 +
 3 files changed, 23 insertions(+), 11 deletions(-)

diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index a043fd4c66..943460fd2c 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -468,6 +468,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 
 %type <range>	OptTempTableName
 %type <into>	into_clause create_as_target create_mv_target
+%type <boolean>	incremental
 
 %type <defelt>	createfunc_opt_item common_func_opt_item dostmt_opt_item
 %type <fun_param> func_arg func_arg_with_default table_func_column aggr_arg
@@ -738,7 +739,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 	HANDLER HAVING HEADER_P HOLD HOUR_P
 
 	IDENTITY_P IF_P ILIKE IMMEDIATE IMMUTABLE IMPLICIT_P IMPORT_P IN_P INCLUDE
-	INCLUDING INCREMENT INDENT INDEX INDEXES INHERIT INHERITS INITIALLY INLINE_P
+	INCLUDING INCREMENT INCREMENTAL INDENT INDEX INDEXES INHERIT INHERITS INITIALLY INLINE_P
 	INNER_P INOUT INPUT_P INSENSITIVE INSERT INSTEAD INT_P INTEGER
 	INTERSECT INTERVAL INTO INVOKER IS ISNULL ISOLATION
 
@@ -4803,32 +4804,34 @@ opt_with_data:
  *****************************************************************************/
 
 CreateMatViewStmt:
-		CREATE OptNoLog MATERIALIZED VIEW create_mv_target AS SelectStmt opt_with_data
+		CREATE OptNoLog incremental MATERIALIZED VIEW create_mv_target AS SelectStmt opt_with_data
 				{
 					CreateTableAsStmt *ctas = makeNode(CreateTableAsStmt);
 
-					ctas->query = $7;
-					ctas->into = $5;
+					ctas->query = $8;
+					ctas->into = $6;
 					ctas->objtype = OBJECT_MATVIEW;
 					ctas->is_select_into = false;
 					ctas->if_not_exists = false;
 					/* cram additional flags into the IntoClause */
-					$5->rel->relpersistence = $2;
-					$5->skipData = !($8);
+					$6->rel->relpersistence = $2;
+					$6->skipData = !($9);
+					$6->ivm = $3;
 					$$ = (Node *) ctas;
 				}
-		| CREATE OptNoLog MATERIALIZED VIEW IF_P NOT EXISTS create_mv_target AS SelectStmt opt_with_data
+		| CREATE OptNoLog incremental MATERIALIZED VIEW IF_P NOT EXISTS create_mv_target AS SelectStmt opt_with_data
 				{
 					CreateTableAsStmt *ctas = makeNode(CreateTableAsStmt);
 
-					ctas->query = $10;
-					ctas->into = $8;
+					ctas->query = $11;
+					ctas->into = $9;
 					ctas->objtype = OBJECT_MATVIEW;
 					ctas->is_select_into = false;
 					ctas->if_not_exists = true;
 					/* cram additional flags into the IntoClause */
-					$8->rel->relpersistence = $2;
-					$8->skipData = !($11);
+					$9->rel->relpersistence = $2;
+					$9->skipData = !($12);
+					$9->ivm = $3;
 					$$ = (Node *) ctas;
 				}
 		;
@@ -4845,9 +4848,14 @@ create_mv_target:
 					$$->tableSpaceName = $5;
 					$$->viewQuery = NULL;		/* filled at analysis time */
 					$$->skipData = false;		/* might get changed later */
+					$$->ivm = false;
 				}
 		;
 
+incremental:	INCREMENTAL				{ $$ = true; }
+				| /*EMPTY*/				{ $$ = false; }
+		;
+
 OptNoLog:	UNLOGGED					{ $$ = RELPERSISTENCE_UNLOGGED; }
 			| /*EMPTY*/					{ $$ = RELPERSISTENCE_PERMANENT; }
 		;
@@ -17686,6 +17694,7 @@ unreserved_keyword:
 			| INCLUDE
 			| INCLUDING
 			| INCREMENT
+			| INCREMENTAL
 			| INDENT
 			| INDEX
 			| INDEXES
@@ -18274,6 +18283,7 @@ bare_label_keyword:
 			| INCLUDE
 			| INCLUDING
 			| INCREMENT
+			| INCREMENTAL
 			| INDENT
 			| INDEX
 			| INDEXES
diff --git a/src/include/nodes/primnodes.h b/src/include/nodes/primnodes.h
index ea47652adb..6f01300a30 100644
--- a/src/include/nodes/primnodes.h
+++ b/src/include/nodes/primnodes.h
@@ -168,6 +168,7 @@ typedef struct IntoClause
 	/* materialized view's SELECT query */
 	Node	   *viewQuery pg_node_attr(query_jumble_ignore);
 	bool		skipData;		/* true for WITH NO DATA */
+	bool		ivm;			/* true for WITH IVM */
 } IntoClause;
 
 
diff --git a/src/include/parser/kwlist.h b/src/include/parser/kwlist.h
index f7fe834cf4..1625fea602 100644
--- a/src/include/parser/kwlist.h
+++ b/src/include/parser/kwlist.h
@@ -210,6 +210,7 @@ PG_KEYWORD("in", IN_P, RESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("include", INCLUDE, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("including", INCLUDING, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("increment", INCREMENT, UNRESERVED_KEYWORD, BARE_LABEL)
+PG_KEYWORD("incremental", INCREMENTAL, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("indent", INDENT, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("index", INDEX, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("indexes", INDEXES, UNRESERVED_KEYWORD, BARE_LABEL)
-- 
2.25.1


--Multipart=_Tue__2_Jul_2024_17_03_11_+0900_6OrVBZxOB4o_k6A1--





^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 2648+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 2648+ messages in thread