Release date: 2012-09-24
This release contains a variety of fixes from 9.2.0. For information about new features in the 9.2 major release, see Section E.109.
A dump/restore is not required for those running 9.2.X.
However, you may need to perform
VACUUM operations to recover from the effects
of the data corruption bug described in the first changelog
Fix persistence marking of shared buffers during WAL replay (Jeff Davis)
This mistake can result in buffers not being written out during checkpoints, resulting in data corruption if the server later crashes without ever having written those buffers. Corruption can occur on any server following crash recovery, but it is significantly more likely to occur on standby slave servers since those perform much more WAL replay. There is a low probability of corruption of btree and GIN indexes. There is a much higher probability of corruption of table “visibility maps”, which might lead to wrong answers from index-only scans. Table data proper cannot be corrupted by this bug.
While no index corruption due to this bug is known to
have occurred in the field, as a precautionary measure it
is recommended that production installations
REINDEX all btree and GIN indexes at a
convenient time after upgrading to 9.2.1.
Also, it is recommended to perform a
VACUUM of all tables while having
vacuum_freeze_table_age set to zero. This will
fix any incorrect visibility map data.
vacuum_cost_delay can be adjusted to reduce
the performance impact of vacuuming, while causing it to
take longer to finish.
Fix possible incorrect sorting of output from queries
Fix planner failure for queries involving
GROUP BY expressions along with window
functions and aggregates (Tom Lane)
Fix planner's assignment of executor parameters (Tom Lane)
This error could result in wrong answers from queries
that scan the same
subquery multiple times.
Improve planner's handling of join conditions in index scans (Tom Lane)
Improve selectivity estimation for text search queries
involving prefixes, i.e.
:* patterns (Tom Lane)
Fix delayed recognition of permissions changes (Tom Lane)
A command that needed no locks other than ones its
transaction already had might fail to notice a concurrent
REVOKE that committed since the start of
ANALYZE to not fail
when a column is a domain over an array type (Tom
Prevent PL/Perl from crashing if a recursive PL/Perl function is redefined while being executed (Tom Lane)
Work around possible misoptimization in PL/Perl (Tom Lane)
Some Linux distributions contain an incorrect version
pthread.h that results
in incorrect compiled code in PL/Perl, leading to crashes
if a PL/Perl function calls another one that throws an
Remove unnecessary dependency on pg_config from pg_upgrade (Peter Eisentraut)
Update time zone data files to tzdata release 2012f for DST law changes in Fiji
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