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<sect1 id="release-9-2-5">
<title>Release 9.2.5</title>
<note>
<title>Release Date</title>
<simpara>2013-10-10</simpara>
</note>
<para>
This release contains a variety of fixes from 9.2.4.
For information about new features in the 9.2 major release, see
<xref linkend="release-9-2">.
</para>
<sect2>
<title>Migration to Version 9.2.5</title>
<para>
A dump/restore is not required for those running 9.2.X.
</para>
<para>
Also, if you are upgrading from a version earlier than 9.2.2,
see the release notes for 9.2.2.
</para>
</sect2>
<sect2>
<title>Changes</title>
<itemizedlist>
<listitem>
<para>
Prevent downcasing of non-ASCII non-double-quoted identifiers in
multi-byte encodings (Andrew Dunstan)
</para>
<para>
The previous behavior was wrong and confusing.
</para>
</listitem>
<listitem>
<para>
Fix memory leak when creating range indexes (Heikki Linnakangas)
</para>
</listitem>
<listitem>
<para>
Fix checkpoint memory leak in background writer when <literal>wal_level =
hot_standby</> (Naoya Anzai)
</para>
</listitem>
<listitem>
<para>
Fix memory leak caused by <function>lo_open()</function> failure
(Heikki Linnakangas)
</para>
</listitem>
<listitem>
<para>
Fix memory overcommit bug when <varname>work_mem</> is using more
than 24GB of memory (Stephen Frost)
</para>
</listitem>
<listitem>
<para>
Serializable snapshot fixes (Kevin Grittner, Heikki Linnakangas)
</para>
</listitem>
<listitem>
<para>
Fix libpq SSL deadlock bug (Stephen Frost)
</para>
</listitem>
<listitem>
<para>
Fix possible SSL network stack corruption in threaded libpq applications
(Nick Phillips, Stephen Frost)
</para>
</listitem>
<listitem>
<para>
Improve estimate of planner cost when choosing between generic and
custom plans (Tom Lane)
</para>
<para>
This change will favor generic plans when planning cost is high.
</para>
</listitem>
<listitem>
<para>
Properly compute row estimates for boolean columns containing many NULL
values (Andrew Gierth)
</para>
<para>
Previously tests like <literal>col IS NOT TRUE</> and <literal>col IS
NOT FALSE</> did not properly factor in NULL values when estimating
plan costs.
</para>
</listitem>
<listitem>
<para>
Fix <literal>UNION ALL</> and inheritance queries to properly
recheck parameterized paths (Tom Lane)
</para>
<para>
This fixes cases where suboptimal query plans could potentially be
chosen.
</para>
</listitem>
<listitem>
<para>
Prevent pushing down <literal>WHERE</> clauses into unsafe
<literal>UNION/INTERSECT</> subqueries (Tom Lane)
</para>
<para>
Previously such push downs could generate errors.
</para>
</listitem>
<listitem>
<para>
Fix rare <literal>GROUP BY</> query error caused by improperly
processed data type modifiers (Tom Lane)
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</para>
</listitem>
<listitem>
<para>
Fix <application>pg_dump</> of foreign tables with dropped columns (Andrew Dunstan)
</para>
<para>
Previously such cases could cause a <application>pg_upgrade</> error.
</para>
</listitem>
<listitem>
<para>
Reorder <application>pg_dump</> processing of extension-related
rules and event triggers (Joe Conway)
</para>
</listitem>
<listitem>
<para>
Force dumping of extension tables if specified by <command>pg_dump
-t</> or <literal>-n</> (Joe Conway)
</para>
</listitem>
<listitem>
<para>
Allow view dump code to better handle dropped columns on base tables
(Tom Lane)
</para>
</listitem>
<listitem>
<para>
Fix <command>pg_restore -l</> with the directory archive to display
the correct format name (Fujii Masao)
</para>
</listitem>
<listitem>
<para>
Properly record index comments created using <literal>UNIQUE</>
and <literal>PRIMARY KEY</> syntax (Andres Freund)
</para>
<para>
This fixes a parallel <application>pg_restore</> failure.
</para>
</listitem>
<listitem>
<para>
Cause <command>pg_basebackup -x</> with an empty xlog directory
to throw an error rather than crashing (Magnus Hagander, Haruka
Takatsuka)
</para>
</listitem>
<listitem>
<para>
Properly guarantee transmission of WAL files before clean switchover
(Fujii Masao)
</para>
<para>
Previously, the streaming replication connection might close before all
WAL files had been replayed on the standby.
</para>
</listitem>
<listitem>
<para>
Improve WAL segment timeline handling during recovery (Heikki
Linnakangas)
</para>
</listitem>
<listitem>
<para>
Fix <command>REINDEX TABLE</> and <command>REINDEX DATABASE</>
to properly revalidate constraints and mark invalidated indexes as
valid (Noah Misch)
</para>
<para>
<command>REINDEX INDEX</> has always worked properly.
</para>
</listitem>
<listitem>
<para>
Avoid deadlocks during insertion into SP-GiST indexes (Teodor Sigaev)
</para>
</listitem>
<listitem>
<para>
Fix possible deadlock during concurrent <command>CREATE INDEX
CONCURRENTLY</> operations (Tom Lane)
</para>
</listitem>
<listitem>
<para>
Fix GiST index lookup crash (Tom Lane)
</para>
</listitem>
<listitem>
<para>
Fix <function>regexp_matches()</> handling of zero-length matches
(Jeevan Chalke)
</para>
<para>
Previously, zero-length matches like '^' could return too many matches.
</para>
</listitem>
<listitem>
<para>
Fix crash for overly-complex regular expressions (Heikki Linnakangas)
</para>
</listitem>
<listitem>
<para>
Fix regular expression match failures for back references combined with
non-greedy quantifiers (Jeevan Chalke)
</para>
</listitem>
<listitem>
<para>
Prevent <command>CREATE FUNCTION</> from checking <command>SET</>
variables unless function body checking is enabled (Tom Lane)
</para>
</listitem>
<listitem>
<para>
Allow <command>ALTER DEFAULT PRIVILEGES</> to operate on schemas
without requiring CREATE permission (Tom Lane)
</para>
</listitem>
<listitem>
<para>
Loosen restriction on keywords used in queries (Tom Lane)
</para>
<para>
Specifically, lessen keyword restrictions for role names, language
names, <command>EXPLAIN</> and <command>COPY</> options, and
<command>SET</> values. This allows <literal>COPY ... (FORMAT
BINARY)</> previously <literal>BINARY</> required single-quotes.
</para>
</listitem>
<listitem>
<para>
Print proper line number during <command>COPY</> failure (Heikki
Linnakangas)
</para>
</listitem>
<listitem>
<para>
Fix <function>pgp_pub_decrypt()</> so it works for secret keys with
passwords (Marko Kreen)
</para>
</listitem>
<listitem>
<para>
Have <application>pg_upgrade</> use <command>>pg_dump
--quote-all-identifiers</> to avoid problems with keyword changes
between releases (Tom Lane)
</para>
</listitem>
<listitem>
<para>
Remove rare inaccurate warning during vacuum of index-less tables
(Heikki Linnakangas)
</para>
</listitem>
<listitem>
<para>
Improve analyze statistics generation after a cancelled file truncate
request (Kevin Grittner)
</para>
</listitem>
<listitem>
<para>
Avoid possible failure when performing transaction control commands (e.g
<command>ROLLBACK</>) in prepared queries (Tom Lane)
</para>
</listitem>
<listitem>
<para>
Allow various spellings of infinity on all platforms (Tom Lane)
</para>
<para>
Supported infinity values are "inf", "+inf", "-inf", "infinity",
"+infinity", and "-infinity".
</para>
</listitem>
<listitem>
<para>
Avoid unnecessary reporting when <varname>track_activities</> is off
(Tom Lane)
</para>
</listitem>
<listitem>
<para>
Expand ability to compare rows to records and arrays (Rafal Rzepecki,
Tom Lane)
</para>
</listitem>
<listitem>
<para>
Prevent crash when <application>psql</>'s <envar>PSQLRC</> variable
contains a tilde (Bruce Momjian)
</para>
</listitem>
<listitem>
<para>
Add spinlock support for ARM64 (Mark Salter)
</para>
</listitem>
<listitem>
<para>
Update time zone data files to <application>tzdata</> release 2013d
for DST law changes in DST law changes in Israel, Morocco, Palestine,
Paraguay. Also, historical zone data corrections for Macquarie Island
(Tom Lane)
</para>
</listitem>
</itemizedlist>
</sect2>
</sect1>
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<sect1 id="release-9-2-4">
<title>Release 9.2.4</title>
<note>
<title>Release Date</title>
<simpara>2013-04-04</simpara>
</note>
<para>
This release contains a variety of fixes from 9.2.3.
For information about new features in the 9.2 major release, see
<xref linkend="release-9-2">.
</para>
<sect2>
<title>Migration to Version 9.2.4</title>
<para>
A dump/restore is not required for those running 9.2.X.
</para>
<para>
However, this release corrects several errors in management of GiST
indexes. After installing this update, it is advisable to
<command>REINDEX</> any GiST indexes that meet one or more of the
conditions described below.
</para>
<para>
Also, if you are upgrading from a version earlier than 9.2.2,
see the release notes for 9.2.2.
</para>
</sect2>
<sect2>
<title>Changes</title>
<itemizedlist>
<listitem>
<para>
Fix insecure parsing of server command-line switches (Mitsumasa
Kondo, Kyotaro Horiguchi)
</para>
<para>
A connection request containing a database name that begins with
<quote><literal>-</></quote> could be crafted to damage or destroy
files within the server's data directory, even if the request is
eventually rejected. (CVE-2013-1899)
</para>
</listitem>
<listitem>
<para>
Reset OpenSSL randomness state in each postmaster child process
(Marko Kreen)
</para>
<para>
This avoids a scenario wherein random numbers generated by
<filename>contrib/pgcrypto</> functions might be relatively easy for
another database user to guess. The risk is only significant when
the postmaster is configured with <varname>ssl</> = <literal>on</>
but most connections don't use SSL encryption. (CVE-2013-1900)
</para>
</listitem>
<listitem>
<para>
Make REPLICATION privilege checks test current user not authenticated
user (Noah Misch)
</para>
<para>
An unprivileged database user could exploit this mistake to call
<function>pg_start_backup()</> or <function>pg_stop_backup()</>,
thus possibly interfering with creation of routine backups.
(CVE-2013-1901)
</para>
</listitem>
<listitem>
<para>
Fix GiST indexes to not use <quote>fuzzy</> geometric comparisons when
it's not appropriate to do so (Alexander Korotkov)
</para>
<para>
The core geometric types perform comparisons using <quote>fuzzy</>
equality, but <function>gist_box_same</> must do exact comparisons,
else GiST indexes using it might become inconsistent. After installing
this update, users should <command>REINDEX</> any GiST indexes on
<type>box</>, <type>polygon</>, <type>circle</>, or <type>point</>
columns, since all of these use <function>gist_box_same</>.
</para>
</listitem>
<listitem>
<para>
Fix erroneous range-union and penalty logic in GiST indexes that use
<filename>contrib/btree_gist</> for variable-width data types, that is
<type>text</>, <type>bytea</>, <type>bit</>, and <type>numeric</>
columns (Tom Lane)
</para>
<para>
These errors could result in inconsistent indexes in which some keys
that are present would not be found by searches, and also in useless
index bloat. Users are advised to <command>REINDEX</> such indexes
after installing this update.
</para>
</listitem>
<listitem>
<para>
Fix bugs in GiST page splitting code for multi-column indexes
(Tom Lane)
</para>
<para>
These errors could result in inconsistent indexes in which some keys
that are present would not be found by searches, and also in indexes
that are unnecessarily inefficient to search. Users are advised to
<command>REINDEX</> multi-column GiST indexes after installing this
update.
</para>
</listitem>
<listitem>
<para>
Fix <function>gist_point_consistent</>
to handle fuzziness consistently (Alexander Korotkov)
</para>
<para>
Index scans on GiST indexes on <type>point</> columns would sometimes
yield results different from a sequential scan, because
<function>gist_point_consistent</> disagreed with the underlying
operator code about whether to do comparisons exactly or fuzzily.
</para>
</listitem>
<listitem>
<para>
Fix buffer leak in WAL replay (Heikki Linnakangas)
</para>
<para>
This bug could result in <quote>incorrect local pin count</> errors
during replay, making recovery impossible.
</para>
</listitem>
<listitem>
<para>
Ensure we do crash recovery before entering archive recovery, if the
database was not stopped cleanly and a <filename>recovery.conf</> file
is present (Heikki Linnakangas, Kyotaro Horiguchi, Mitsumasa Kondo)
</para>
<para>
This is needed to ensure that the database is consistent in certain
scenarios, such as initializing a standby server with a filesystem
snapshot from a running server.
</para>
</listitem>
<listitem>
<para>
Avoid deleting not-yet-archived WAL files during crash recovery
(Heikki Linnakangas, Fujii Masao)
</para>
</listitem>
<listitem>
<para>
Fix race condition in <command>DELETE RETURNING</> (Tom Lane)
</para>
<para>
Under the right circumstances, <command>DELETE RETURNING</> could
attempt to fetch data from a shared buffer that the current process
no longer has any pin on. If some other process changed the buffer
meanwhile, this would lead to garbage <literal>RETURNING</> output, or
even a crash.
</para>
</listitem>
<listitem>
<para>
Fix infinite-loop risk in regular expression compilation (Tom Lane,
Don Porter)
</para>
</listitem>
<listitem>
<para>
Fix potential null-pointer dereference in regular expression compilation
(Tom Lane)
</para>
</listitem>
<listitem>
<para>
Fix <function>to_char()</> to use ASCII-only case-folding rules where
appropriate (Tom Lane)
</para>
<para>
This fixes misbehavior of some template patterns that should be
locale-independent, but mishandled <quote><literal>I</></quote> and
<quote><literal>i</></quote> in Turkish locales.
</para>
</listitem>
<listitem>
<para>
Fix unwanted rejection of timestamp <literal>1999-12-31 24:00:00</>
(Tom Lane)
</para>
</listitem>
<listitem>
<para>
Fix SQL-language functions to be safely usable as support
functions for range types (Tom Lane)
</para>
</listitem>
<listitem>
<para>
Fix logic error when a single transaction does <command>UNLISTEN</>
then <command>LISTEN</> (Tom Lane)
</para>
<para>
The session wound up not listening for notify events at all, though it
surely should listen in this case.
</para>
</listitem>
<listitem>
<para>
Fix possible planner crash after columns have been added to a view
that's depended on by another view (Tom Lane)
</para>
</listitem>
<listitem>
<para>
Fix performance issue in <literal>EXPLAIN (ANALYZE, TIMING OFF)</>
(Pavel Stehule)
</para>
</listitem>
<listitem>
<para>
Remove useless <quote>picksplit doesn't support secondary split</> log
messages (Josh Hansen, Tom Lane)
</para>
<para>
This message seems to have been added in expectation of code that was
never written, and probably never will be, since GiST's default
handling of secondary splits is actually pretty good. So stop nagging
end users about it.
</para>
</listitem>
<listitem>
<para>
Remove vestigial secondary-split support in
<function>gist_box_picksplit()</> (Tom Lane)
</para>
<para>
Not only was this implementation of secondary-split not better than the
default implementation, it's actually worse. So remove it and let the
default code path handle the case.
</para>
</listitem>
<listitem>
<para>
Fix possible failure to send a session's last few transaction
commit/abort counts to the statistics collector (Tom Lane)
</para>
</listitem>
<listitem>
<para>
Eliminate memory leaks in PL/Perl's <function>spi_prepare()</> function
(Alex Hunsaker, Tom Lane)
</para>
</listitem>
<listitem>
<para>
Fix <application>pg_dumpall</> to handle database names containing
<quote><literal>=</></quote> correctly (Heikki Linnakangas)
</para>
</listitem>
<listitem>
<para>
Avoid crash in <application>pg_dump</> when an incorrect connection
string is given (Heikki Linnakangas)
</para>
</listitem>
<listitem>
<para>
Ignore invalid indexes in <application>pg_dump</> and
<application>pg_upgrade</> (Michael Paquier, Bruce Momjian)
</para>
<para>
Dumping invalid indexes can cause problems at restore time, for example
if the reason the index creation failed was because it tried to enforce
a uniqueness condition not satisfied by the table's data. Also, if the
index creation is in fact still in progress, it seems reasonable to
consider it to be an uncommitted DDL change, which
<application>pg_dump</> wouldn't be expected to dump anyway.
<application>pg_upgrade</> now also skips invalid indexes rather than
failing.
</para>
</listitem>
<listitem>
<para>
In <application>pg_basebackup</>, include only the current server
version's subdirectory when backing up a tablespace (Heikki
Linnakangas)
</para>
</listitem>
<listitem>
<para>
Add a server version check in <application>pg_basebackup</> and
<application>pg_receivexlog</>, so they fail cleanly with version
combinations that won't work (Heikki Linnakangas)
</para>
</listitem>
<listitem>
<para>
Fix <filename>contrib/dblink</> to handle inconsistent settings of
<varname>DateStyle</> or <varname>IntervalStyle</> safely (Daniel
Farina, Tom Lane)
</para>
<para>
Previously, if the remote server had different settings of these
parameters, ambiguous dates might be read incorrectly. This fix
ensures that datetime and interval columns fetched by a
<filename>dblink</> query will be interpreted correctly. Note however
that inconsistent settings are still risky, since literal values
appearing in SQL commands sent to the remote server might be
interpreted differently than they would be locally.
</para>
</listitem>
<listitem>
<para>
Fix <filename>contrib/pg_trgm</>'s <function>similarity()</> function
to return zero for trigram-less strings (Tom Lane)
</para>
<para>
Previously it returned <literal>NaN</> due to internal division by zero.
</para>
</listitem>
<listitem>
<para>
Enable building <productname>PostgreSQL</> with Microsoft Visual
Studio 2012 (Brar Piening, Noah Misch)
</para>
</listitem>
<listitem>
<para>
Update time zone data files to <application>tzdata</> release 2013b
for DST law changes in Chile, Haiti, Morocco, Paraguay, and some
Russian areas. Also, historical zone data corrections for numerous
places.
</para>
<para>
Also, update the time zone abbreviation files for recent changes in
Russia and elsewhere: <literal>CHOT</>, <literal>GET</>,
<literal>IRKT</>, <literal>KGT</>, <literal>KRAT</>, <literal>MAGT</>,
<literal>MAWT</>, <literal>MSK</>, <literal>NOVT</>, <literal>OMST</>,
<literal>TKT</>, <literal>VLAT</>, <literal>WST</>, <literal>YAKT</>,
<literal>YEKT</> now follow their current meanings, and
<literal>VOLT</> (Europe/Volgograd) and <literal>MIST</>
(Antarctica/Macquarie) are added to the default abbreviations list.
</para>
</listitem>
</itemizedlist>
</sect2>
</sect1>
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<sect1 id="release-9-2-3">
<title>Release 9.2.3</title>
<note>
<title>Release Date</title>
<simpara>2013-02-07</simpara>
</note>
<para>
This release contains a variety of fixes from 9.2.2.
For information about new features in the 9.2 major release, see
<xref linkend="release-9-2">.
</para>
<sect2>
<title>Migration to Version 9.2.3</title>
<para>
A dump/restore is not required for those running 9.2.X.
</para>
<para>
However, if you are upgrading from a version earlier than 9.2.2,
see the release notes for 9.2.2.
</para>
</sect2>
<sect2>
<title>Changes</title>
<itemizedlist>
<listitem>
<para>
Prevent execution of <function>enum_recv</> from SQL (Tom Lane)
</para>
<para>
The function was misdeclared, allowing a simple SQL command to crash the
server. In principle an attacker might be able to use it to examine the
contents of server memory. Our thanks to Sumit Soni (via Secunia SVCRP)
for reporting this issue. (CVE-2013-0255)
</para>
</listitem>
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<listitem>
<para>
Fix multiple problems in detection of when a consistent database
state has been reached during WAL replay (Fujii Masao, Heikki
Linnakangas, Simon Riggs, Andres Freund)
</para>
</listitem>
<listitem>
<para>
Fix detection of end-of-backup point when no actual redo work is
required (Heikki Linnakangas)
</para>
<para>
This mistake could result in incorrect <quote>WAL ends before end of
online backup</> errors.
</para>
</listitem>
<listitem>
<para>
Update minimum recovery point when truncating a relation file (Heikki
Linnakangas)
</para>
<para>
Once data has been discarded, it's no longer safe to stop recovery at
an earlier point in the timeline.
</para>
</listitem>
<listitem>
<para>
Fix recycling of WAL segments after changing recovery target timeline
(Heikki Linnakangas)
</para>
</listitem>
<listitem>
<para>
Properly restore timeline history files from archive on cascading
standby servers (Heikki Linnakangas)
</para>
</listitem>
<listitem>
<para>
Fix lock conflict detection on hot-standby servers (Andres Freund,
Robert Haas)
</para>
</listitem>
<listitem>
<para>
Fix missing cancellations in hot standby mode (Noah Misch, Simon Riggs)
</para>
<para>
The need to cancel conflicting hot-standby queries would sometimes be
missed, allowing those queries to see inconsistent data.
</para>
</listitem>
<listitem>
<para>
Prevent recovery pause feature from pausing before users can connect
(Tom Lane)
</para>
</listitem>
<listitem>
<para>
Fix SQL grammar to allow subscripting or field selection from a
sub-SELECT result (Tom Lane)
</para>
</listitem>
<listitem>
<para>
Fix performance problems with autovacuum truncation in busy workloads
(Jan Wieck)
</para>
<para>
Truncation of empty pages at the end of a table requires exclusive
lock, but autovacuum was coded to fail (and release the table lock)
when there are conflicting lock requests. Under load, it is easily
possible that truncation would never occur, resulting in table bloat.
Fix by performing a partial truncation, releasing the lock, then
attempting to re-acquire the lock and continue. This fix also greatly
reduces the average time before autovacuum releases the lock after a
conflicting request arrives.
</para>
</listitem>
<listitem>
<para>
Improve performance of <function>SPI_execute</> and related
functions, thereby improving PL/pgSQL's <literal>EXECUTE</>
(Heikki Linnakangas, Tom Lane)
</para>
<para>
Remove some data-copying overhead that was added in 9.2 as a
consequence of revisions in the plan caching mechanism. This
eliminates a performance regression compared to 9.1, and also saves
memory, especially when the query string to be executed contains many
SQL statements.
</para>
<para>
A side benefit is that multi-statement query strings are now
processed fully serially, that is we complete execution of earlier
statements before running parse analysis and planning on the
following ones. This eliminates a long-standing issue, in that DDL
that should affect the behavior of a later statement will now behave as
expected.
</para>
</listitem>
<listitem>
<para>
Restore pre-9.2 cost estimates for index usage (Tom Lane)
</para>
<para>
An ill-considered change of a fudge factor led to undesirably high
cost estimates for use of very large indexes.
</para>
</listitem>
<listitem>
<para>
Fix intermittent crash in <literal>DROP INDEX CONCURRENTLY</> (Tom Lane)
</para>
</listitem>
<listitem>
<para>
Fix potential corruption of shared-memory lock table during
<command>CREATE/DROP INDEX CONCURRENTLY</> (Tom Lane)
</para>
</listitem>
<listitem>
<para>