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Tom Lane 8f29467c57 Change "long" numGroups fields to be Cardinality (i.e., double).
We've been nibbling away at removing uses of "long" for a long time,
since its width is platform-dependent.  Here's one more: change the
remaining "long" fields in Plan nodes to Cardinality, since the three
surviving examples all represent group-count estimates.  The upstream
planner code was converted to Cardinality some time ago; for example
the corresponding fields in Path nodes are type Cardinality, as are
the arguments of the make_foo_path functions.  Downstream in the
executor, it turns out that these all feed to the table-size argument
of BuildTupleHashTable.  Change that to "double" as well, and fix it
so that it safely clamps out-of-range values to the uint32 limit of
simplehash.h, as was not being done before.

Essentially, this is removing all the artificial datatype-dependent
limitations on these values from upstream processing, and applying
just one clamp at the moment where we're forced to do so by the
datatype choices of simplehash.h.

Also, remove BuildTupleHashTable's misguided attempt to enforce
work_mem/hash_mem_limit.  It doesn't have enough information
(particularly not the expected tuple width) to do that accurately,
and it has no real business second-guessing the caller's choice.
For all these plan types, it's really the planner's responsibility
to not choose a hashed implementation if the hashtable is expected
to exceed hash_mem_limit.  The previous patch improved the
accuracy of those estimates, and even if BuildTupleHashTable had
more information it should arrive at the same conclusions.

Reported-by: Jeff Janes <jeff.janes@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/CAMkU=1zia0JfW_QR8L5xA2vpa0oqVuiapm78h=WpNsHH13_9uw@mail.gmail.com
2025-11-02 16:57:43 -05:00
.github Add CODE_OF_CONDUCT.md, CONTRIBUTING.md, and SECURITY.md. 2024-07-02 13:03:58 -05:00
config Remove traces of support for Sun Studio compiler 2025-09-12 07:39:05 +02:00
contrib Fix contrib/ltree's subpath() with negative offset. 2025-11-01 13:25:42 -04:00
doc Mark function arguments of type "Datum *" as "const Datum *" where possible 2025-10-31 10:47:25 +01:00
src Change "long" numGroups fields to be Cardinality (i.e., double). 2025-11-02 16:57:43 -05:00
.cirrus.star ci: Simplify ci-os-only handling 2025-08-14 12:09:34 -04:00
.cirrus.tasks.yml ci: macos: Upgrade to Sequoia 2025-10-30 16:08:21 -04:00
.cirrus.yml ci: Per-repo configuration for manually trigger tasks 2025-08-14 11:54:03 -04:00
.dir-locals.el Make Emacs perl-mode indent more like perltidy. 2019-01-13 11:32:31 -08:00
.editorconfig Add script to keep .editorconfig in sync with .gitattributes 2025-02-01 10:09:45 +01:00
.git-blame-ignore-revs Add previous commit to .git-blame-ignore-revs. 2025-10-21 10:02:19 -05:00
.gitattributes Fix git whitespace warning 2025-08-15 10:32:35 +02:00
.gitignore Update top-level .gitignore. 2022-12-04 15:23:00 -05:00
.mailmap Add a Git .mailmap file 2024-11-05 13:56:02 +01:00
aclocal.m4 autoconf: Move export_dynamic determination to configure 2022-12-06 18:55:28 -08:00
configure Use C11 char16_t and char32_t for Unicode code points. 2025-10-29 14:17:13 -07:00
configure.ac Use C11 char16_t and char32_t for Unicode code points. 2025-10-29 14:17:13 -07:00
COPYRIGHT Align organization wording in copyright statement 2025-05-16 11:20:07 -04:00
GNUmakefile.in Allow selecting the git revision to be packaged by "make dist". 2024-05-03 11:08:50 -04:00
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.build Use C11 char16_t and char32_t for Unicode code points. 2025-10-29 14:17:13 -07:00
meson_options.txt Add support for basic NUMA awareness 2025-04-07 23:08:17 +02:00
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/.