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Tom Lane 7122f9d543 Fix bit-rotted planner test case. 
While fooling with my pet outer-join-variables patch, I discovered
that the test case I added in commit 11086f2f2 no longer demonstrates
what it's supposed to.  The idea is to tempt the planner to reverse
the order of the two outer joins, which would leave noplace to
correctly evaluate the WHERE clause that's inserted between them.
Before the addition of the delay_upper_joins mechanism, it would
have taken the bait.

However, subsequent improvements broke the test in two different ways.
First, we now recognize the IS NULL coding pattern as an antijoin, and
we won't re-order antijoins; even if we did, the IS NULL test clauses
get removed so there would be no opportunity for them to misbehave.
Second, the planner now discovers that nested parameterized indexscans
are a lot cheaper than the double hash join it used back in the day,
and that approach doesn't want to re-order the joins anyway.  Thus,
in HEAD the test passes even if one dikes out delay_upper_joins.

To fix, change the IS NULL tests to COALESCE clauses, which produce
the same results but the planner isn't smart enough to convert them
to antijoins.  It'll still go for parameterized indexscans though,
so drop the index enabling that (don't know why I added that in the
first place), and disable nestloop joining just to be sure.

This time around, add an EXPLAIN to make the choice of plan visible.
2022-12-17 18:51:24 -05:00
config autoconf: Move export_dynamic determination to configure 2022-12-06 18:55:28 -08:00
contrib C comment: fix wording 2022-12-16 12:15:54 -05:00
doc pg_upgrade: Add --copy option 2022-12-16 18:32:02 +01:00
src Fix bit-rotted planner test case. 2022-12-17 18:51:24 -05:00
.cirrus.yml Add option to specify segment size in blocks 2022-12-07 19:32:59 -08:00
.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 b2e6e7682 to .git-blame-ignore-revs 2022-09-08 14:06:59 +07:00
.gitattributes Remove trailing whitespace from *.sgml files. 2022-04-20 11:04:49 -04:00
.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 Disable clang 16's -Wcast-function-type-strict. 2022-12-13 10:15:56 +13:00
configure.ac Disable clang 16's -Wcast-function-type-strict. 2022-12-13 10:15:56 +13:00
COPYRIGHT Update copyright for 2022 2022-01-07 19:04:57 -05:00
GNUmakefile.in Remove temporary portlock directory during make [dist]clean. 2022-11-26 10:30:31 -05:00
HISTORY Canonicalize some URLs 2020-02-10 20:47:50 +01:00
Makefile Dynamically find correct installation docs in Makefile. 2022-01-19 14:48:25 +01:00
meson_options.txt Add option to specify segment size in blocks 2022-12-07 19:32:59 -08:00
meson.build Disable clang 16's -Wcast-function-type-strict. 2022-12-13 10:15:56 +13:00
README Canonicalize some URLs 2020-02-10 20:47:50 +01:00
README.git Canonicalize some URLs 2020-02-10 20:47:50 +01:00

README 

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.

PostgreSQL has many language interfaces, many of which are listed here:

	https://www.postgresql.org/download/

See the file INSTALL for instructions on how to build and install
PostgreSQL.  That file also lists supported operating systems and
hardware platforms and contains information regarding any other
software packages that are required to build or run the PostgreSQL
system.  Copyright and license information can be found in the
file COPYRIGHT.  A comprehensive documentation set is included in this
distribution; it can be read as described in the installation
instructions.

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