rdelaage/postgresql
1
0
Fork 0
mirror of https://git.postgresql.org/git/postgresql.git synced 2024-08-22 01:43:22 +02:00
Code Issues Packages Projects Releases Wiki Activity
44,425 Commits 36 Branches 606 Tags 423 MiB
C 86%
PLpgSQL 5.5%
Perl 4.1%
Yacc 1.3%
Makefile 0.7%
Other 2.3%
5748f3a0aa
Go to file
Tom Lane 5748f3a0aa Improve predtest.c's internal docs, and enhance its functionality a bit. 
Commit b08df9cab left things rather poorly documented as far as the
exact semantics of "clause_is_check" mode went.  Also, that mode did
not really work correctly for predicate_refuted_by; although given the
lack of specification as to what it should do, as well as the lack
of any actual use-case, that's perhaps not surprising.

Rename "clause_is_check" to "weak" proof mode, and provide specifications
for what it should do.  I defined weak refutation as meaning "truth of A
implies non-truth of B", which makes it possible to use the mode in the
part of relation_excluded_by_constraints that checks for mutually
contradictory WHERE clauses.  Fix up several places that did things wrong
for that definition.  (As far as I can see, these errors would only lead
to failure-to-prove, not incorrect claims of proof, making them not
serious bugs even aside from the fact that v10 contains no use of this
mode.  So there seems no need for back-patching.)

In addition, teach predicate_refuted_by_recurse that it can use
predicate_implied_by_recurse after all when processing a strong NOT-clause,
so long as it asks for the correct proof strength.  This is an optimization
that could have been included in commit b08df9cab, but wasn't.

Also, simplify and generalize the logic that checks for whether nullness of
the argument of IS [NOT] NULL would force overall nullness of the predicate
or clause.  (This results in a change in the partition_prune test's output,
as it is now able to prune an all-nulls partition that it did not recognize
before.)

In passing, in PartConstraintImpliedByRelConstraint, remove bogus
conversion of the constraint list to explicit-AND form and then right back
again; that accomplished nothing except forcing a useless extra level of
recursion inside predicate_implied_by.

Discussion: https://postgr.es/m/5983.1520487191@sss.pgh.pa.us
2018-03-09 16:58:26 -05:00
config Extend configure's __int128 test to check for a known gcc bug. 2018-01-18 11:09:44 -05:00
contrib Revert "Temporarily instrument postgres_fdw test to look for statistics changes." 2018-03-08 11:33:27 -05:00
doc Fix cross-checking of ReservedBackends/max_wal_senders/MaxConnections. 2018-03-08 11:25:26 -05:00
src Improve predtest.c's internal docs, and enhance its functionality a bit. 2018-03-09 16:58:26 -05:00
.dir-locals.el emacs: Set indent-tabs-mode in perl-mode 2015-04-12 23:53:23 -04:00
.gitattributes Remove contrib/tsearch2. 2017-02-13 11:06:11 -05:00
.gitignore Add lcov --initial 2017-09-29 08:54:34 -04:00
aclocal.m4 Make configure check for IPC::Run when --enable-tap-tests is specified. 2017-06-15 15:56:12 -04:00
configure Tests for Kerberos/GSSAPI authentication 2018-03-06 10:57:36 -05:00
configure.in Tests for Kerberos/GSSAPI authentication 2018-03-06 10:57:36 -05:00
COPYRIGHT Update copyright for 2018 2018-01-02 23:30:12 -05:00
GNUmakefile.in Have "make coverage" recurse into contrib as well 2016-09-05 18:44:36 -03:00
HISTORY Change documentation references to PG website to use https: not http: 2017-05-20 21:50:47 -04:00
Makefile Fix non-GNU makefiles for AIX make. 2017-11-30 00:57:22 -08:00
README Change documentation references to PG website to use https: not http: 2017-05-20 21:50:47 -04:00
README.git Change documentation references to PG website to use https: not http: 2017-05-20 21:50:47 -04:00

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/.