Go to file
Tom Lane a65724dfa7 Propagate pathkeys from CTEs up to the outer query.
If we know the sort order of a CTE's output, and it is relevant
to the outer query, label the CTE's outer-query access path using
those pathkeys.  This may enable optimizations such as avoiding
a sort in the outer query.

The code for hoisting pathkeys into the outer query already exists
for regular RTE_SUBQUERY subqueries, but it wasn't getting used for
CTEs, possibly out of concern for maintaining an optimization fence
between the CTE and the outer query.  However, on the same arguments
used for commit f7816aec2, there seems no harm in letting the outer
query know what the inner query decided to do.

In support of this, we now remember the best Path as well as Plan
for each subquery for the rest of the planner run.  There may be
future applications for having that at hand, and it surely costs
little to build one more List.

Richard Guo (minor mods by me)

Discussion: https://postgr.es/m/CAMbWs49xYd3f8CrE8-WW3--dV1zH_sDSDn-vs2DzHj81Wcnsew@mail.gmail.com
2024-03-26 13:05:51 -04:00
config Remove AIX support 2024-02-28 15:17:23 +04:00
contrib Avoid edge case in pg_visibility test with small shared_buffers 2024-03-25 20:19:43 -07:00
doc Adjust pgbench option for debug mode. 2024-03-25 11:08:53 -05:00
src Propagate pathkeys from CTEs up to the outer query. 2024-03-26 13:05:51 -04:00
.cirrus.star Remove duplicate words in docs and code comments. 2023-10-09 09:18:47 +05:30
.cirrus.tasks.yml ci: macos: Choose python version 2024-03-25 16:39:08 -07:00
.cirrus.yml ci: Make compute resources for CI configurable 2023-08-23 15:15:28 -07:00
.dir-locals.el Make Emacs perl-mode indent more like perltidy. 2019-01-13 11:32:31 -08:00
.editorconfig Add .editorconfig 2019-12-18 09:13:13 +01:00
.git-blame-ignore-revs Add a few recent commits to .git-blame-ignore-revs. 2024-03-05 14:15:06 -06:00
.gitattributes Remove non-existing file from .gitattributes 2024-02-16 11:39:09 +01:00
.gitignore Update top-level .gitignore. 2022-12-04 15:23:00 -05:00
aclocal.m4 autoconf: Move export_dynamic determination to configure 2022-12-06 18:55:28 -08:00
configure Add --copy-file-range option to pg_upgrade. 2024-03-06 12:01:01 +13:00
configure.ac Add --copy-file-range option to pg_upgrade. 2024-03-06 12:01:01 +13:00
COPYRIGHT Update copyright for 2024 2024-01-03 20:49:05 -05:00
GNUmakefile.in make dist uses git archive 2024-03-25 06:29:53 +01:00
HISTORY Canonicalize some URLs 2020-02-10 20:47:50 +01:00
Makefile Remove AIX support 2024-02-28 15:17:23 +04:00
meson_options.txt Add backend support for injection points 2024-01-22 10:15:50 +09:00
meson.build make dist uses git archive 2024-03-25 06:29:53 +01:00
README.md Revise the style of a paragraph in README.md. 2024-03-21 10:16:41 -05:00

PostgreSQL Database Management System

This directory contains the source code distribution of the PostgreSQL database management system.

PostgreSQL is an advanced object-relational database management system that supports an extended subset of the SQL standard, including transactions, foreign keys, subqueries, triggers, user-defined types and functions. This distribution also contains C language bindings.

Copyright and license information can be found in the file COPYRIGHT.

General documentation about this version of PostgreSQL can be found at https://www.postgresql.org/docs/devel/. In particular, information about building PostgreSQL from the source code can be found at https://www.postgresql.org/docs/devel/installation.html.

The latest version of this software, and related software, may be obtained at https://www.postgresql.org/download/. For more information look at our web site located at https://www.postgresql.org/.