postgresql

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Tom Lane a4523c5aa5 Improve planning of btree index scans using ScalarArrayOpExpr quals. Since we taught btree to handle ScalarArrayOpExpr quals natively (commit `9e8da0f757`), the planner has always included ScalarArrayOpExpr quals in index conditions if possible. However, if the qual is for a non-first index column, this could result in an inferior plan because we can no longer take advantage of index ordering (cf. commit `807a40c551`). It can be better to omit the ScalarArrayOpExpr qual from the index condition and let it be done as a filter, so that the output doesn't need to get sorted. Indeed, this is true for the query introduced as a test case by the latter commit. To fix, restructure get_index_paths and build_index_paths so that we consider paths both with and without ScalarArrayOpExpr quals in non-first index columns. Redesign the API of build_index_paths so that it reports what it found, saving useless second or third calls. Report and patch by Andrew Gierth (though rather heavily modified by me). Back-patch to 9.2 where this code was introduced, since the issue can result in significant performance regressions compared to plans produced by 9.1 and earlier.		2014-10-26 16:12:22 -04:00
config	Add a basic atomic ops API abstracting away platform/architecture details.	2014-09-25 23:49:05 +02:00
contrib	pg_test_fsync: Update output format	2014-10-20 15:36:51 -04:00
doc	Allow input format xxxx-xxxx-xxxx for macaddr type	2014-10-21 16:16:39 -04:00
src	Improve planning of btree index scans using ScalarArrayOpExpr quals.	2014-10-26 16:12:22 -04:00
.dir-locals.el	Update Emacs configuration	2013-08-13 20:08:44 -04:00
.gitattributes	Add functions for dealing with PGP armor header lines to pgcrypto.	2014-10-01 16:03:39 +03:00
.gitignore	Add *.pot to .gitignore	2013-10-19 10:56:52 -04:00
aclocal.m4
configure	Add native compiler and memory barriers for solaris studio.	2014-10-25 11:11:39 +02:00
configure.in	Add native compiler and memory barriers for solaris studio.	2014-10-25 11:11:39 +02:00
COPYRIGHT	Update copyright for 2014	2014-01-07 16:05:30 -05:00
GNUmakefile.in	Add TAP tests for client programs	2014-04-14 21:33:46 -04:00
HISTORY	Improve text of stub HISTORY file.	2014-02-12 18:16:17 -05:00
Makefile	Allow make check in PL directories	2011-02-15 06:52:12 +02:00
README	Don't generate plain-text HISTORY and src/test/regress/README anymore.	2014-02-10 20:48:04 -05:00
README.git	Don't generate plain-text HISTORY and src/test/regress/README anymore.	2014-02-10 20:48:04 -05:00

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:

	http://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
http://www.postgresql.org/download/.  For more information look at our
web site located at http://www.postgresql.org/.