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* Potential typo in abbreviated insertion query
@ 2020-12-28 02:32 PG Doc comments form <noreply@postgresql.org>
0 siblings, 1 reply; 3+ messages in thread
From: PG Doc comments form @ 2020-12-28 02:32 UTC (permalink / raw)
To: pgsql-docs@lists.postgresql.org; +Cc: fotis.koutoupas@gmail.com
The following documentation comment has been logged on the website:
Page: https://www.postgresql.org/docs/13/executor.html
Description:
It's located within the parentheses of the last paragraph.
>(A simple INSERT ... VALUES command creates a trivial plan tree consisting
of a single Result node, which computes just one result row, and ModifyTable
above it to perform the insertion. But INSERT ... SELECT can demand the full
power of the executor mechanism.)
I'm under the impression that the second inline code block refers to `INSERT
... VALUES`.
^ permalink raw reply [nested|flat] 3+ messages in thread
* Re: Potential typo in abbreviated insertion query
@ 2020-12-31 18:44 Bruce Momjian <bruce@momjian.us>
parent: PG Doc comments form <noreply@postgresql.org>
0 siblings, 1 reply; 3+ messages in thread
From: Bruce Momjian @ 2020-12-31 18:44 UTC (permalink / raw)
To: fotis.koutoupas@gmail.com; pgsql-docs@lists.postgresql.org
On Mon, Dec 28, 2020 at 02:32:35AM +0000, PG Doc comments form wrote:
> The following documentation comment has been logged on the website:
>
> Page: https://www.postgresql.org/docs/13/executor.html
> Description:
>
> It's located within the parentheses of the last paragraph.
>
> >(A simple INSERT ... VALUES command creates a trivial plan tree consisting
> of a single Result node, which computes just one result row, and ModifyTable
> above it to perform the insertion. But INSERT ... SELECT can demand the full
> power of the executor mechanism.)
>
> I'm under the impression that the second inline code block refers to `INSERT
> ... VALUES`.
I think the text is correct, but I also think it is trying to do too
much in one paragraph. Here is a doc patch to improve this.
--
Bruce Momjian <bruce@momjian.us> https://momjian.us
EnterpriseDB https://enterprisedb.com
The usefulness of a cup is in its emptiness, Bruce Lee
Attachments:
executor.diff (text/x-diff, 3.5K) download
diff --git a/doc/src/sgml/arch-dev.sgml b/doc/src/sgml/arch-dev.sgml
new file mode 100644
index 7883c3c..ade0ad9
*** a/doc/src/sgml/arch-dev.sgml
--- b/doc/src/sgml/arch-dev.sgml
***************
*** 529,554 ****
</para>
<para>
! The executor mechanism is used to evaluate all four basic SQL query types:
! <command>SELECT</command>, <command>INSERT</command>, <command>UPDATE</command>, and
! <command>DELETE</command>. For <command>SELECT</command>, the top-level executor
! code only needs to send each row returned by the query plan tree off
! to the client. For <command>INSERT</command>, each returned row is inserted
! into the target table specified for the <command>INSERT</command>. This is
! done in a special top-level plan node called <literal>ModifyTable</literal>.
! (A simple
! <command>INSERT ... VALUES</command> command creates a trivial plan tree
! consisting of a single <literal>Result</literal> node, which computes just one
! result row, and <literal>ModifyTable</literal> above it to perform the insertion.
! But <command>INSERT ... SELECT</command> can demand the full power
! of the executor mechanism.) For <command>UPDATE</command>, the planner arranges
! that each computed row includes all the updated column values, plus
! the <firstterm>TID</firstterm> (tuple ID, or row ID) of the original target row;
! this data is fed into a <literal>ModifyTable</literal> node, which uses the
! information to create a new updated row and mark the old row deleted.
! For <command>DELETE</command>, the only column that is actually returned by the
! plan is the TID, and the <literal>ModifyTable</literal> node simply uses the TID
! to visit each target row and mark it deleted.
</para>
</sect1>
--- 529,564 ----
</para>
<para>
! The executor mechanism is used to evaluate all four basic SQL query
! types: <command>SELECT</command>, <command>INSERT</command>,
! <command>UPDATE</command>, and <command>DELETE</command>.
! For <command>SELECT</command>, the top-level executor code
! only needs to send each row returned by the query plan tree
! off to the client. <command>INSERT ... SELECT</command>,
! <command>UPDATE</command>, and <command>DELETE</command>
! are effectively <command>SELECT</command>s under a special
! top-level plan node called <literal>ModifyTable</literal>.
! </para>
!
! <para>
! <command>INSERT ... SELECT</command> feeds the rows up
! to <literal>ModifyTable</literal> for insertion. For
! <command>UPDATE</command>, the planner arranges that each
! computed row includes all the updated column values, plus the
! <firstterm>TID</firstterm> (tuple ID, or row ID) of the original
! target row; this data is fed up to the <literal>ModifyTable</literal>
! node, which uses the information to create a new updated row and
! mark the old row deleted. For <command>DELETE</command>, the only
! column that is actually returned by the plan is the TID, and the
! <literal>ModifyTable</literal> node simply uses the TID to visit each
! target row and mark it deleted.
! </para>
!
! <para>
! A simple <command>INSERT ... VALUES</command> command creates a
! trivial plan tree consisting of a single <literal>Result</literal>
! node, which computes just one result row, feeding that up
! to<literal>ModifyTable</literal> to perform the insertion.
</para>
</sect1>
* Re: Potential typo in abbreviated insertion query
@ 2021-01-09 17:11 Bruce Momjian <bruce@momjian.us>
parent: Bruce Momjian <bruce@momjian.us>
0 siblings, 0 replies; 3+ messages in thread
From: Bruce Momjian @ 2021-01-09 17:11 UTC (permalink / raw)
To: fotis.koutoupas@gmail.com; pgsql-docs@lists.postgresql.org
On Thu, Dec 31, 2020 at 01:44:56PM -0500, Bruce Momjian wrote:
> On Mon, Dec 28, 2020 at 02:32:35AM +0000, PG Doc comments form wrote:
> > The following documentation comment has been logged on the website:
> >
> > Page: https://www.postgresql.org/docs/13/executor.html
> > Description:
> >
> > It's located within the parentheses of the last paragraph.
> >
> > >(A simple INSERT ... VALUES command creates a trivial plan tree consisting
> > of a single Result node, which computes just one result row, and ModifyTable
> > above it to perform the insertion. But INSERT ... SELECT can demand the full
> > power of the executor mechanism.)
> >
> > I'm under the impression that the second inline code block refers to `INSERT
> > ... VALUES`.
>
> I think the text is correct, but I also think it is trying to do too
> much in one paragraph. Here is a doc patch to improve this.
Patch applied to all supported branches.
--
Bruce Momjian <bruce@momjian.us> https://momjian.us
EnterpriseDB https://enterprisedb.com
The usefulness of a cup is in its emptiness, Bruce Lee
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2020-12-28 02:32 Potential typo in abbreviated insertion query PG Doc comments form <noreply@postgresql.org>
2020-12-31 18:44 ` Bruce Momjian <bruce@momjian.us>
2021-01-09 17:11 ` Bruce Momjian <bruce@momjian.us>
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