postgresql/contrib
Tom Lane d3b0a23a20 Repair pg_upgrade's failure to preserve relfrozenxid for matviews.
This oversight led to data corruption in matviews, manifesting as
"could not access status of transaction" before our most recent releases,
and "found xmin from before relfrozenxid" errors since then.

The proximate cause of the problem seems to have been confusion between
the task of preserving dropped-column status and the task of preserving
frozenxid status.  Those are required for distinct sets of relkinds,
and the reasoning was entirely undocumented in the source code.  In hopes
of forestalling future errors of the same kind, try to improve the
commentary in this area.

In passing, also improve the remarkably unhelpful comments around
pg_upgrade's set_frozenxids().  That's not actually buggy AFAICS,
but good luck figuring out what it does from the old comments.

Per report from Claudio Freire.  It appears that bug #14852 from Alexey
Ermakov is an earlier report of the same issue, and there may be other
cases that we failed to identify at the time.

Patch by me based on analysis by Andres Freund.  The bug dates back
to the introduction of matviews, so back-patch to all supported branches.

Discussion: https://postgr.es/m/CAGTBQpbrY9CdRGGhyBZ9yqY4jWaGC85rUF4X+R7d-aim=mBNsw@mail.gmail.com
Discussion: https://postgr.es/m/20171013115320.28049.86457@wrigleys.postgresql.org
2018-02-21 18:40:24 -05:00
..
adminpack Fix pg_file_write() error handling. 2017-03-12 19:36:15 -04:00
auth_delay Limit values of archive_timeout, post_auth_delay, auth_delay.milliseconds. 2012-11-18 17:15:06 -05:00
auto_explain Fix failure of contrib/auto_explain to print per-node timing information. 2014-09-19 13:19:02 -04:00
btree_gin Make contrib regression tests safe for Danish locale. 2016-07-21 16:52:36 -04:00
btree_gist Ensure plan stability in contrib/btree_gist regression test. 2016-05-12 20:04:41 -04:00
chkpass Fix volatility markings of some contrib I/O functions. 2014-11-05 11:34:19 -05:00
citext Make contrib regression tests safe for Danish locale. 2016-07-21 16:52:36 -04:00
cube Fix typos in comments. 2017-02-06 11:34:28 +02:00
dblink Fix ancient connection leak in dblink 2017-03-11 13:33:22 -08:00
dict_int Fix typos in some error messages thrown by extension scripts when fed to psql. 2014-08-25 18:30:46 +02:00
dict_xsyn Fix typos in some error messages thrown by extension scripts when fed to psql. 2014-08-25 18:30:46 +02:00
dummy_seclabel Update copyrights for 2013 2013-01-01 17:15:01 -05:00
earthdistance Fix typos in comments. 2017-02-06 11:34:28 +02:00
file_fdw Fix contrib/file_fdw's expected file 2015-03-06 11:47:09 -03:00
fuzzystrmatch Add missing va_end() call to a early exit in dmetaphone.c's StringAt(). 2015-01-04 15:35:47 +01:00
hstore Avoid formally-undefined use of memcpy() in hstoreUniquePairs(). 2017-11-25 14:42:46 -05:00
intagg Fix typos in some error messages thrown by extension scripts when fed to psql. 2014-08-25 18:30:46 +02:00
intarray Fix -e option in contrib/intarray/bench/bench.pl. 2016-08-17 15:51:10 -04:00
isn Fix typos in comments. 2017-02-06 11:34:28 +02:00
lo Fix typos in some error messages thrown by extension scripts when fed to psql. 2014-08-25 18:30:46 +02:00
ltree Spelling fixes 2017-03-14 13:45:45 -04:00
oid2name Remove tabs after spaces in C comments 2014-05-06 11:26:28 -04:00
pageinspect Remove unused macros. 2016-05-02 10:09:03 +03:00
passwordcheck Update copyrights for 2013 2013-01-01 17:15:01 -05:00
pg_archivecleanup Fix new warnings from GCC 7 2017-05-15 13:31:38 -04:00
pg_buffercache Fix typos in some error messages thrown by extension scripts when fed to psql. 2014-08-25 18:30:46 +02:00
pg_freespacemap Fix typos in some error messages thrown by extension scripts when fed to psql. 2014-08-25 18:30:46 +02:00
pg_standby Fix new warnings from GCC 7 2017-05-15 13:31:38 -04:00
pg_stat_statements Avoid unlikely data-loss scenarios due to rename() without fsync. 2016-03-09 18:53:54 -08:00
pg_test_fsync Avoid depending on non-POSIX behavior of fcntl(2). 2017-04-21 15:55:56 -04:00
pg_test_timing Correctly handle test durations of more than 2147s in pg_test_timing. 2015-01-04 15:53:08 +01:00
pg_trgm Further fix pg_trgm's extraction of trigrams from regular expressions. 2017-04-14 14:52:03 -04:00
pg_upgrade Repair pg_upgrade's failure to preserve relfrozenxid for matviews. 2018-02-21 18:40:24 -05:00
pg_upgrade_support Update copyrights for 2013 2013-01-01 17:15:01 -05:00
pg_xlogdump pg_xlogdump: Remove extra newline in error message 2017-03-08 09:59:52 -05:00
pgbench Fix "pg_bench -C -M prepared". 2016-03-16 23:18:07 -04:00
pgcrypto pgcrypto's encrypt() supports AES-128, AES-192, and AES-256 2018-01-31 16:33:46 -05:00
pgrowlocks Fix handling of multixacts predating pg_upgrade 2016-06-24 18:29:28 -04:00
pgstattuple Remove unused macros. 2016-05-02 10:09:03 +03:00
postgres_fdw Stabilize postgres_fdw regression tests. 2017-07-21 14:20:43 -04:00
seg Fix typos in comments. 2017-02-06 11:34:28 +02:00
sepgsql Silence compiler warning in sepgsql 2017-04-06 14:24:50 -07:00
spi Fix typos in comments. 2017-02-06 11:34:28 +02:00
sslinfo Fix error message wording in previous sslinfo commit 2015-09-08 11:10:20 -03:00
start-scripts Provide modern examples of how to auto-start Postgres on macOS. 2017-11-17 12:47:44 -05:00
tablefunc Handle unexpected query results, especially NULLs, safely in connectby(). 2015-01-29 20:18:40 -05:00
tcn Remove tabs after spaces in C comments 2014-05-06 11:26:28 -04:00
test_parser Fix typos in some error messages thrown by extension scripts when fed to psql. 2014-08-25 18:30:46 +02:00
tsearch2 Fix typos in comments. 2017-02-06 11:34:28 +02:00
unaccent Fix typos in some error messages thrown by extension scripts when fed to psql. 2014-08-25 18:30:46 +02:00
uuid-ossp Fix typos in some error messages thrown by extension scripts when fed to psql. 2014-08-25 18:30:46 +02:00
vacuumlo pgindent run for release 9.3 2013-05-29 16:58:43 -04:00
worker_spi worker_spi: Call pgstat_report_stat. 2016-09-28 12:40:23 -04:00
xml2 Fix typos in comments. 2017-02-06 11:34:28 +02:00
contrib-global.mk Remove cvs keywords from all files. 2010-09-20 22:08:53 +02:00
Makefile contrib/Makefile also needs updated 2013-02-22 18:56:42 -03:00
README Update contrib/README 2012-04-14 09:29:54 +03:00

The PostgreSQL contrib tree
---------------------------

This subtree contains porting tools, analysis utilities, and plug-in
features that are not part of the core PostgreSQL system, mainly
because they address a limited audience or are too experimental to be
part of the main source tree.  This does not preclude their
usefulness.

User documentation for each module appears in the main SGML
documentation.

When building from the source distribution, these modules are not
built automatically, unless you build the "world" target.  You can
also build and install them all by running "gmake all" and "gmake
install" in this directory; or to build and install just one selected
module, do the same in that module's subdirectory.

Some directories supply new user-defined functions, operators, or
types.  To make use of one of these modules, after you have installed
the code you need to register the new SQL objects in the database
system by executing a CREATE EXTENSION command.  In a fresh database,
you can simply do

    CREATE EXTENSION module_name;

See the PostgreSQL documentation for more information about this
procedure.