Peter Geoghegan 486c2ea25c Fix nbtree array unsatisfied inequality check. _bt_advance_array_keys didn't take sufficient care at the point where it decides whether to start a new primitive index scan based on a call to _bt_check_compare against finaltup (a call with the scan direction flipped around). The final decision was conditioned on rules about how the scan key offset sktrig that initially triggered array advancement (passed to _bt_advance_array_keys from its _bt_checkkeys caller) compared to the offset set by its own _bt_check_compare finaltup call. This approach was faulty, in that it allowed _bt_advance_array_keys to incorrectly start a new primitive index scan, that landed on the same leaf page (on assert-enabled builds it led to an assertion failure). In general, scans with array keys are expected to never have to read the same leaf page more than once (barring cases involving cursors, and cases where the scan restores a marked position for the inner side of a merge join). This principle was established by commit `5bf748b8`. To fix, make the final decision based on whether the scan key offset set by the _bt_check_compare finaltup call is an offset to an inequality strategy scan key. An unsatisfied required inequality strategy scan key indicates that all of the scan's required equality strategy scan keys must also be satisfied by finaltup (not just by caller's tuple), and that there is a decent chance that _bt_first will be able to reposition the scan to a position many leaf pages ahead of the current leaf page. Oversight in commit `5bf748b8`. Discussion: https://postgr.es/m/CAH2-Wz=DyHbcg7o6zXqzyiin8WE8vzk4tvU8Lrnh-a=EAvO0TQ@mail.gmail.com		2 years ago
config	jit: Remove {llvm-config,clang}-N configure probes.	2 years ago
contrib	Unify some error messages	2 years ago
doc	doc PG 17 relnotes: wording improvements, add links, merge item	2 years ago
src	Fix nbtree array unsatisfied inequality check.	2 years ago
.cirrus.star	Remove duplicate words in docs and code comments.	2 years ago
.cirrus.tasks.yml	ci: windows: Use the same image for VS and MinGW tasks	2 years ago
.cirrus.yml	ci: Make compute resources for CI configurable	3 years ago
.dir-locals.el	…
.editorconfig	…
.git-blame-ignore-revs	Add `da256a4a7` to .git-blame-ignore-revs.	2 years ago
.gitattributes	Remove non-existing file from .gitattributes	2 years ago
.gitignore	…
COPYRIGHT	Update copyright for 2024	2 years ago
GNUmakefile.in	Allow selecting the git revision to be packaged by "make dist".	2 years ago
HISTORY	…
Makefile	Remove AIX support	2 years ago
README.md	Revise the style of a paragraph in README.md.	2 years ago
aclocal.m4	autoconf: Move export_dynamic determination to configure	3 years ago
configure	Stamp 17beta2.	2 years ago
configure.ac	Stamp 17beta2.	2 years ago
meson.build	Stamp 17beta2.	2 years ago
meson_options.txt	Allow selecting the git revision to be packaged by "make dist".	2 years ago

README.md

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.

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/.