2011-04-18 This release contains a variety of fixes from 8.4.7. For information about new features in the 8.4 major release, see . A dump/restore is not required for those running 8.4.X. However, if your installation was upgraded from a previous major release by running pg_upgrade, you should take action to prevent possible data loss due to a now-fixed bug in pg_upgrade. The recommended solution is to run VACUUM FREEZE on all TOAST tables. More information is available at http://wiki.postgresql.org/wiki/20110408pg_upgrade_fix. Also, if you are upgrading from a version earlier than 8.4.2, see the release notes for 8.4.2. Fix pg_upgrade's handling of TOAST tables (Bruce Momjian) The pg_class.relfrozenxid value for TOAST tables was not correctly copied into the new installation during pg_upgrade. This could later result in pg_clog files being discarded while they were still needed to validate tuples in the TOAST tables, leading to could not access status of transaction failures. This error poses a significant risk of data loss for installations that have been upgraded with pg_upgrade. This patch corrects the problem for future uses of pg_upgrade, but does not in itself cure the issue in installations that have been processed with a buggy version of pg_upgrade. Suppress incorrect PD_ALL_VISIBLE flag was incorrectly set warning (Heikki Linnakangas) VACUUM would sometimes issue this warning in cases that are actually valid. Disallow including a composite type in itself (Tom Lane) This prevents scenarios wherein the server could recurse infinitely while processing the composite type. While there are some possible uses for such a structure, they don't seem compelling enough to justify the effort required to make sure it always works safely. Avoid potential deadlock during catalog cache initialization (Nikhil Sontakke) In some cases the cache loading code would acquire share lock on a system index before locking the index's catalog. This could deadlock against processes trying to acquire exclusive locks in the other, more standard order. Fix dangling-pointer problem in BEFORE ROW UPDATE trigger handling when there was a concurrent update to the target tuple (Tom Lane) This bug has been observed to result in intermittent cannot extract system attribute from virtual tuple failures while trying to do UPDATE RETURNING ctid. There is a very small probability of more serious errors, such as generating incorrect index entries for the updated tuple. Disallow DROP TABLE when there are pending deferred trigger events for the table (Tom Lane) Formerly the DROP would go through, leading to could not open relation with OID nnn errors when the triggers were eventually fired. Prevent crash triggered by constant-false WHERE conditions during GEQO optimization (Tom Lane) Improve planner's handling of semi-join and anti-join cases (Tom Lane) Fix selectivity estimation for text search to account for NULLs (Jesper Krogh) Improve PL/pgSQL's ability to handle row types with dropped columns (Pavel Stehule) This is a back-patch of fixes previously made in 9.0. Fix PL/Python memory leak involving array slices (Daniel Popowich) Fix pg_restore to cope with long lines (over 1KB) in TOC files (Tom Lane) Put in more safeguards against crashing due to division-by-zero with overly enthusiastic compiler optimization (Aurelien Jarno) Support use of dlopen() in FreeBSD and OpenBSD on MIPS (Tom Lane) There was a hard-wired assumption that this system function was not available on MIPS hardware on these systems. Use a compile-time test instead, since more recent versions have it. Fix compilation failures on HP-UX (Heikki Linnakangas) Fix version-incompatibility problem with libintl on Windows (Hiroshi Inoue) Fix usage of xcopy in Windows build scripts to work correctly under Windows 7 (Andrew Dunstan) This affects the build scripts only, not installation or usage. Fix path separator used by pg_regress on Cygwin (Andrew Dunstan) Update time zone data files to tzdata release 2011f for DST law changes in Chile, Cuba, Falkland Islands, Morocco, Samoa, and Turkey; also historical corrections for South Australia, Alaska, and Hawaii. 2011-01-31 This release contains a variety of fixes from 8.4.6. For information about new features in the 8.4 major release, see . A dump/restore is not required for those running 8.4.X. However, if you are upgrading from a version earlier than 8.4.2, see the release notes for 8.4.2. Avoid failures when EXPLAIN tries to display a simple-form CASE expression (Tom Lane) If the CASE's test expression was a constant, the planner could simplify the CASE into a form that confused the expression-display code, resulting in unexpected CASE WHEN clause errors. Fix assignment to an array slice that is before the existing range of subscripts (Tom Lane) If there was a gap between the newly added subscripts and the first pre-existing subscript, the code miscalculated how many entries needed to be copied from the old array's null bitmap, potentially leading to data corruption or crash. Avoid unexpected conversion overflow in planner for very distant date values (Tom Lane) The date type supports a wider range of dates than can be represented by the timestamp types, but the planner assumed it could always convert a date to timestamp with impunity. Fix pg_restore's text output for large objects (BLOBs) when standard_conforming_strings is on (Tom Lane) Although restoring directly to a database worked correctly, string escaping was incorrect if pg_restore was asked for SQL text output and standard_conforming_strings had been enabled in the source database. Fix erroneous parsing of tsquery values containing ... & !(subexpression) | ... (Tom Lane) Queries containing this combination of operators were not executed correctly. The same error existed in contrib/intarray's query_int type and contrib/ltree's ltxtquery type. Fix buffer overrun in contrib/intarray's input function for the query_int type (Apple) This bug is a security risk since the function's return address could be overwritten. Thanks to Apple Inc's security team for reporting this issue and supplying the fix. (CVE-2010-4015) Fix bug in contrib/seg's GiST picksplit algorithm (Alexander Korotkov) This could result in considerable inefficiency, though not actually incorrect answers, in a GiST index on a seg column. If you have such an index, consider REINDEXing it after installing this update. (This is identical to the bug that was fixed in contrib/cube in the previous update.) 2010-12-16 This release contains a variety of fixes from 8.4.5. For information about new features in the 8.4 major release, see . A dump/restore is not required for those running 8.4.X. However, if you are upgrading from a version earlier than 8.4.2, see the release notes for 8.4.2. Force the default wal_sync_method to be fdatasync on Linux (Tom Lane, Marti Raudsepp) The default on Linux has actually been fdatasync for many years, but recent kernel changes caused PostgreSQL to choose open_datasync instead. This choice did not result in any performance improvement, and caused outright failures on certain filesystems, notably ext4 with the data=journal mount option. Fix assorted bugs in WAL replay logic for GIN indexes (Tom Lane) This could result in bad buffer id: 0 failures or corruption of index contents during replication. Fix recovery from base backup when the starting checkpoint WAL record is not in the same WAL segment as its redo point (Jeff Davis) Fix persistent slowdown of autovacuum workers when multiple workers remain active for a long time (Tom Lane) The effective vacuum_cost_limit for an autovacuum worker could drop to nearly zero if it processed enough tables, causing it to run extremely slowly. Add support for detecting register-stack overrun on IA64 (Tom Lane) The IA64 architecture has two hardware stacks. Full prevention of stack-overrun failures requires checking both. Add a check for stack overflow in copyObject() (Tom Lane) Certain code paths could crash due to stack overflow given a sufficiently complex query. Fix detection of page splits in temporary GiST indexes (Heikki Linnakangas) It is possible to have a concurrent page split in a temporary index, if for example there is an open cursor scanning the index when an insertion is done. GiST failed to detect this case and hence could deliver wrong results when execution of the cursor continued. Fix error checking during early connection processing (Tom Lane) The check for too many child processes was skipped in some cases, possibly leading to postmaster crash when attempting to add the new child process to fixed-size arrays. Improve efficiency of window functions (Tom Lane) Certain cases where a large number of tuples needed to be read in advance, but work_mem was large enough to allow them all to be held in memory, were unexpectedly slow. percent_rank(), cume_dist() and ntile() in particular were subject to this problem. Avoid memory leakage while ANALYZE'ing complex index expressions (Tom Lane) Ensure an index that uses a whole-row Var still depends on its table (Tom Lane) An index declared like create index i on t (foo(t.*)) would not automatically get dropped when its table was dropped. Do not inline a SQL function with multiple OUT parameters (Tom Lane) This avoids a possible crash due to loss of information about the expected result rowtype. Behave correctly if ORDER BY, LIMIT, FOR UPDATE, or WITH is attached to the VALUES part of INSERT ... VALUES (Tom Lane) Fix constant-folding of COALESCE() expressions (Tom Lane) The planner would sometimes attempt to evaluate sub-expressions that in fact could never be reached, possibly leading to unexpected errors. Fix postmaster crash when connection acceptance (accept() or one of the calls made immediately after it) fails, and the postmaster was compiled with GSSAPI support (Alexander Chernikov) Fix missed unlink of temporary files when log_temp_files is active (Tom Lane) If an error occurred while attempting to emit the log message, the unlink was not done, resulting in accumulation of temp files. Add print functionality for InhRelation nodes (Tom Lane) This avoids a failure when debug_print_parse is enabled and certain types of query are executed. Fix incorrect calculation of distance from a point to a horizontal line segment (Tom Lane) This bug affected several different geometric distance-measurement operators. Fix incorrect calculation of transaction status in ecpg (Itagaki Takahiro) Fix PL/pgSQL's handling of simple expressions to not fail in recursion or error-recovery cases (Tom Lane) Fix PL/Python's handling of set-returning functions (Jan Urbanski) Attempts to call SPI functions within the iterator generating a set result would fail. Fix bug in contrib/cube's GiST picksplit algorithm (Alexander Korotkov) This could result in considerable inefficiency, though not actually incorrect answers, in a GiST index on a cube column. If you have such an index, consider REINDEXing it after installing this update. Don't emit identifier will be truncated notices in contrib/dblink except when creating new connections (Itagaki Takahiro) Fix potential coredump on missing public key in contrib/pgcrypto (Marti Raudsepp) Fix memory leak in contrib/xml2's XPath query functions (Tom Lane) Update time zone data files to tzdata release 2010o for DST law changes in Fiji and Samoa; also historical corrections for Hong Kong. 2010-10-04 This release contains a variety of fixes from 8.4.4. For information about new features in the 8.4 major release, see . A dump/restore is not required for those running 8.4.X. However, if you are upgrading from a version earlier than 8.4.2, see the release notes for 8.4.2. Use a separate interpreter for each calling SQL userid in PL/Perl and PL/Tcl (Tom Lane) This change prevents security problems that can be caused by subverting Perl or Tcl code that will be executed later in the same session under another SQL user identity (for example, within a SECURITY DEFINER function). Most scripting languages offer numerous ways that that might be done, such as redefining standard functions or operators called by the target function. Without this change, any SQL user with Perl or Tcl language usage rights can do essentially anything with the SQL privileges of the target function's owner. The cost of this change is that intentional communication among Perl and Tcl functions becomes more difficult. To provide an escape hatch, PL/PerlU and PL/TclU functions continue to use only one interpreter per session. This is not considered a security issue since all such functions execute at the trust level of a database superuser already. It is likely that third-party procedural languages that claim to offer trusted execution have similar security issues. We advise contacting the authors of any PL you are depending on for security-critical purposes. Our thanks to Tim Bunce for pointing out this issue (CVE-2010-3433). Prevent possible crashes in pg_get_expr() by disallowing it from being called with an argument that is not one of the system catalog columns it's intended to be used with (Heikki Linnakangas, Tom Lane) Treat exit code 128 (ERROR_WAIT_NO_CHILDREN) as non-fatal on Windows (Magnus Hagander) Under high load, Windows processes will sometimes fail at startup with this error code. Formerly the postmaster treated this as a panic condition and restarted the whole database, but that seems to be an overreaction. Fix incorrect placement of placeholder evaluation (Tom Lane) This bug could result in query outputs being non-null when they should be null, in cases where the inner side of an outer join is a sub-select with non-strict expressions in its output list. Fix possible duplicate scans of UNION ALL member relations (Tom Lane) Fix cannot handle unplanned sub-select error (Tom Lane) This occurred when a sub-select contains a join alias reference that expands into an expression containing another sub-select. Fix mishandling of whole-row Vars that reference a view or sub-select and appear within a nested sub-select (Tom Lane) Fix mishandling of cross-type IN comparisons (Tom Lane) This could result in failures if the planner tried to implement an IN join with a sort-then-unique-then-plain-join plan. Fix computation of ANALYZE statistics for tsvector columns (Jan Urbanski) The original coding could produce incorrect statistics, leading to poor plan choices later. Improve planner's estimate of memory used by array_agg(), string_agg(), and similar aggregate functions (Hitoshi Harada) The previous drastic underestimate could lead to out-of-memory failures due to inappropriate choice of a hash-aggregation plan. Fix failure to mark cached plans as transient (Tom Lane) If a plan is prepared while CREATE INDEX CONCURRENTLY is in progress for one of the referenced tables, it is supposed to be re-planned once the index is ready for use. This was not happening reliably. Reduce PANIC to ERROR in some occasionally-reported btree failure cases, and provide additional detail in the resulting error messages (Tom Lane) This should improve the system's robustness with corrupted indexes. Fix incorrect search logic for partial-match queries with GIN indexes (Tom Lane) Cases involving AND/OR combination of several GIN index conditions didn't always give the right answer, and were sometimes much slower than necessary. Prevent show_session_authorization() from crashing within autovacuum processes (Tom Lane) Defend against functions returning setof record where not all the returned rows are actually of the same rowtype (Tom Lane) Fix possible corruption of pending trigger event lists during subtransaction rollback (Tom Lane) This could lead to a crash or incorrect firing of triggers. Fix possible failure when hashing a pass-by-reference function result (Tao Ma, Tom Lane) Improve merge join's handling of NULLs in the join columns (Tom Lane) A merge join can now stop entirely upon reaching the first NULL, if the sort order is such that NULLs sort high. Take care to fsync the contents of lockfiles (both postmaster.pid and the socket lockfile) while writing them (Tom Lane) This omission could result in corrupted lockfile contents if the machine crashes shortly after postmaster start. That could in turn prevent subsequent attempts to start the postmaster from succeeding, until the lockfile is manually removed. Avoid recursion while assigning XIDs to heavily-nested subtransactions (Andres Freund, Robert Haas) The original coding could result in a crash if there was limited stack space. Avoid holding open old WAL segments in the walwriter process (Magnus Hagander, Heikki Linnakangas) The previous coding would prevent removal of no-longer-needed segments. Fix log_line_prefix's %i escape, which could produce junk early in backend startup (Tom Lane) Prevent misinterpretation of partially-specified relation options for TOAST tables (Itagaki Takahiro) In particular, fillfactor would be read as zero if any other reloption had been set for the table, leading to serious bloat. Fix inheritance count tracking in ALTER TABLE ... ADD CONSTRAINT (Robert Haas) Fix possible data corruption in ALTER TABLE ... SET TABLESPACE when archiving is enabled (Jeff Davis) Allow CREATE DATABASE and ALTER DATABASE ... SET TABLESPACE to be interrupted by query-cancel (Guillaume Lelarge) Improve CREATE INDEX's checking of whether proposed index expressions are immutable (Tom Lane) Fix REASSIGN OWNED to handle operator classes and families (Asko Tiidumaa) Fix possible core dump when comparing two empty tsquery values (Tom Lane) Fix LIKE's handling of patterns containing % followed by _ (Tom Lane) We've fixed this before, but there were still some incorrectly-handled cases. Re-allow input of Julian dates prior to 0001-01-01 AD (Tom Lane) Input such as 'J100000'::date worked before 8.4, but was unintentionally broken by added error-checking. Fix PL/pgSQL to throw an error, not crash, if a cursor is closed within a FOR loop that is iterating over that cursor (Heikki Linnakangas) In PL/Python, defend against null pointer results from PyCObject_AsVoidPtr and PyCObject_FromVoidPtr (Peter Eisentraut) In libpq, fix full SSL certificate verification for the case where both host and hostaddr are specified (Tom Lane) Make psql recognize DISCARD ALL as a command that should not be encased in a transaction block in autocommit-off mode (Itagaki Takahiro) Fix some issues in pg_dump's handling of SQL/MED objects (Tom Lane) Notably, pg_dump would always fail if run by a non-superuser, which was not intended. Improve pg_dump and pg_restore's handling of non-seekable archive files (Tom Lane, Robert Haas) This is important for proper functioning of parallel restore. Improve parallel pg_restore's ability to cope with selective restore (-L option) (Tom Lane) The original code tended to fail if the -L file commanded a non-default restore ordering. Fix ecpg to process data from RETURNING clauses correctly (Michael Meskes) Fix some memory leaks in ecpg (Zoltan Boszormenyi) Improve contrib/dblink's handling of tables containing dropped columns (Tom Lane) Fix connection leak after duplicate connection name errors in contrib/dblink (Itagaki Takahiro) Fix contrib/dblink to handle connection names longer than 62 bytes correctly (Itagaki Takahiro) Add hstore(text, text) function to contrib/hstore (Robert Haas) This function is the recommended substitute for the now-deprecated => operator. It was back-patched so that future-proofed code can be used with older server versions. Note that the patch will be effective only after contrib/hstore is installed or reinstalled in a particular database. Users might prefer to execute the CREATE FUNCTION command by hand, instead. Update build infrastructure and documentation to reflect the source code repository's move from CVS to Git (Magnus Hagander and others) Update time zone data files to tzdata release 2010l for DST law changes in Egypt and Palestine; also historical corrections for Finland. This change also adds new names for two Micronesian timezones: Pacific/Chuuk is now preferred over Pacific/Truk (and the preferred abbreviation is CHUT not TRUT) and Pacific/Pohnpei is preferred over Pacific/Ponape. Make Windows' N. Central Asia Standard Time timezone map to Asia/Novosibirsk, not Asia/Almaty (Magnus Hagander) Microsoft changed the DST behavior of this zone in the timezone update from KB976098. Asia/Novosibirsk is a better match to its new behavior. 2010-05-17 This release contains a variety of fixes from 8.4.3. For information about new features in the 8.4 major release, see . A dump/restore is not required for those running 8.4.X. However, if you are upgrading from a version earlier than 8.4.2, see the release notes for 8.4.2. Enforce restrictions in plperl using an opmask applied to the whole interpreter, instead of using Safe.pm (Tim Bunce, Andrew Dunstan) Recent developments have convinced us that Safe.pm is too insecure to rely on for making plperl trustable. This change removes use of Safe.pm altogether, in favor of using a separate interpreter with an opcode mask that is always applied. Pleasant side effects of the change include that it is now possible to use Perl's strict pragma in a natural way in plperl, and that Perl's $a and $b variables work as expected in sort routines, and that function compilation is significantly faster. (CVE-2010-1169) Prevent PL/Tcl from executing untrustworthy code from pltcl_modules (Tom) PL/Tcl's feature for autoloading Tcl code from a database table could be exploited for trojan-horse attacks, because there was no restriction on who could create or insert into that table. This change disables the feature unless pltcl_modules is owned by a superuser. (However, the permissions on the table are not checked, so installations that really need a less-than-secure modules table can still grant suitable privileges to trusted non-superusers.) Also, prevent loading code into the unrestricted normal Tcl interpreter unless we are really going to execute a pltclu function. (CVE-2010-1170) Fix data corruption during WAL replay of ALTER ... SET TABLESPACE (Tom) When archive_mode is on, ALTER ... SET TABLESPACE generates a WAL record whose replay logic was incorrect. It could write the data to the wrong place, leading to possibly-unrecoverable data corruption. Data corruption would be observed on standby slaves, and could occur on the master as well if a database crash and recovery occurred after committing the ALTER and before the next checkpoint. Fix possible crash if a cache reset message is received during rebuild of a relcache entry (Heikki) This error was introduced in 8.4.3 while fixing a related failure. Apply per-function GUC settings while running the language validator for the function (Itagaki Takahiro) This avoids failures if the function's code is invalid without the setting; an example is that SQL functions may not parse if the search_path is not correct. Do constraint exclusion for inherited UPDATE and DELETE target tables when constraint_exclusion = partition (Tom) Due to an oversight, this setting previously only caused constraint exclusion to be checked in SELECT commands. Do not allow an unprivileged user to reset superuser-only parameter settings (Alvaro) Previously, if an unprivileged user ran ALTER USER ... RESET ALL for himself, or ALTER DATABASE ... RESET ALL for a database he owns, this would remove all special parameter settings for the user or database, even ones that are only supposed to be changeable by a superuser. Now, the ALTER will only remove the parameters that the user has permission to change. Avoid possible crash during backend shutdown if shutdown occurs when a CONTEXT addition would be made to log entries (Tom) In some cases the context-printing function would fail because the current transaction had already been rolled back when it came time to print a log message. Fix erroneous handling of %r parameter in recovery_end_command (Heikki) The value always came out zero. Ensure the archiver process responds to changes in archive_command as soon as possible (Tom) Fix pl/pgsql's CASE statement to not fail when the case expression is a query that returns no rows (Tom) Update pl/perl's ppport.h for modern Perl versions (Andrew) Fix assorted memory leaks in pl/python (Andreas Freund, Tom) Handle empty-string connect parameters properly in ecpg (Michael) Prevent infinite recursion in psql when expanding a variable that refers to itself (Tom) Fix psql's \copy to not add spaces around a dot within \copy (select ...) (Tom) Addition of spaces around the decimal point in a numeric literal would result in a syntax error. Avoid formatting failure in psql when running in a locale context that doesn't match the client_encoding (Tom) Fix unnecessary GIN indexes do not support whole-index scans errors for unsatisfiable queries using contrib/intarray operators (Tom) Ensure that contrib/pgstattuple functions respond to cancel interrupts promptly (Tatsuhito Kasahara) Make server startup deal properly with the case that shmget() returns EINVAL for an existing shared memory segment (Tom) This behavior has been observed on BSD-derived kernels including OS X. It resulted in an entirely-misleading startup failure complaining that the shared memory request size was too large. Avoid possible crashes in syslogger process on Windows (Heikki) Deal more robustly with incomplete time zone information in the Windows registry (Magnus) Update the set of known Windows time zone names (Magnus) Update time zone data files to tzdata release 2010j for DST law changes in Argentina, Australian Antarctic, Bangladesh, Mexico, Morocco, Pakistan, Palestine, Russia, Syria, Tunisia; also historical corrections for Taiwan. Also, add PKST (Pakistan Summer Time) to the default set of timezone abbreviations. 2010-03-15 This release contains a variety of fixes from 8.4.2. For information about new features in the 8.4 major release, see . A dump/restore is not required for those running 8.4.X. However, if you are upgrading from a version earlier than 8.4.2, see the release notes for 8.4.2. Add new configuration parameter ssl_renegotiation_limit to control how often we do session key renegotiation for an SSL connection (Magnus) This can be set to zero to disable renegotiation completely, which may be required if a broken SSL library is used. In particular, some vendors are shipping stopgap patches for CVE-2009-3555 that cause renegotiation attempts to fail. Fix possible deadlock during backend startup (Tom) Fix possible crashes due to not handling errors during relcache reload cleanly (Tom) Fix possible crash due to use of dangling pointer to a cached plan (Tatsuo) Fix possible crash due to overenthusiastic invalidation of cached plan for ROLLBACK (Tom) Fix possible crashes when trying to recover from a failure in subtransaction start (Tom) Fix server memory leak associated with use of savepoints and a client encoding different from server's encoding (Tom) Fix incorrect WAL data emitted during end-of-recovery cleanup of a GIST index page split (Yoichi Hirai) This would result in index corruption, or even more likely an error during WAL replay, if we were unlucky enough to crash during end-of-recovery cleanup after having completed an incomplete GIST insertion. Fix bug in WAL redo cleanup method for GIN indexes (Heikki) Fix incorrect comparison of scan key in GIN index search (Teodor) Make substring() for bit types treat any negative length as meaning all the rest of the string (Tom) The previous coding treated only -1 that way, and would produce an invalid result value for other negative values, possibly leading to a crash (CVE-2010-0442). Fix integer-to-bit-string conversions to handle the first fractional byte correctly when the output bit width is wider than the given integer by something other than a multiple of 8 bits (Tom) Fix some cases of pathologically slow regular expression matching (Tom) Fix bug occurring when trying to inline a SQL function that returns a set of a composite type that contains dropped columns (Tom) Fix bug with trying to update a field of an element of a composite-type array column (Tom) Avoid failure when EXPLAIN has to print a FieldStore or assignment ArrayRef expression (Tom) These cases can arise now that EXPLAIN VERBOSE tries to print plan node target lists. Avoid an unnecessary coercion failure in some cases where an undecorated literal string appears in a subquery within UNION/INTERSECT/EXCEPT (Tom) This fixes a regression for some cases that worked before 8.4. Avoid undesirable rowtype compatibility check failures in some cases where a whole-row Var has a rowtype that contains dropped columns (Tom) Fix the STOP WAL LOCATION entry in backup history files to report the next WAL segment's name when the end location is exactly at a segment boundary (Itagaki Takahiro) Always pass the catalog ID to an option validator function specified in CREATE FOREIGN DATA WRAPPER (Martin Pihlak) Fix some more cases of temporary-file leakage (Heikki) This corrects a problem introduced in the previous minor release. One case that failed is when a plpgsql function returning set is called within another function's exception handler. Add support for doing FULL JOIN ON FALSE (Tom) This prevents a regression from pre-8.4 releases for some queries that can now be simplified to a constant-false join condition. Improve constraint exclusion processing of boolean-variable cases, in particular make it possible to exclude a partition that has a bool_column = false constraint (Tom) Prevent treating an INOUT cast as representing binary compatibility (Heikki) Include column name in the message when warning about inability to grant or revoke column-level privileges (Stephen Frost) This is more useful than before and helps to prevent confusion when a REVOKE generates multiple messages, which formerly appeared to be duplicates. When reading pg_hba.conf and related files, do not treat @something as a file inclusion request if the @ appears inside quote marks; also, never treat @ by itself as a file inclusion request (Tom) This prevents erratic behavior if a role or database name starts with @. If you need to include a file whose path name contains spaces, you can still do so, but you must write @"/path to/file" rather than putting the quotes around the whole construct. Prevent infinite loop on some platforms if a directory is named as an inclusion target in pg_hba.conf and related files (Tom) Fix possible infinite loop if SSL_read or SSL_write fails without setting errno (Tom) This is reportedly possible with some Windows versions of openssl. Disallow GSSAPI authentication on local connections, since it requires a hostname to function correctly (Magnus) Protect ecpg against applications freeing strings unexpectedly (Michael) Make ecpg report the proper SQLSTATE if the connection disappears (Michael) Fix translation of cell contents in psql \d output (Heikki) Fix psql's numericlocale option to not format strings it shouldn't in latex and troff output formats (Heikki) Fix a small per-query memory leak in psql (Tom) Make psql return the correct exit status (3) when ON_ERROR_STOP and --single-transaction are both specified and an error occurs during the implied COMMIT (Bruce) Fix pg_dump's output of permissions for foreign servers (Heikki) Fix possible crash in parallel pg_restore due to out-of-range dependency IDs (Tom) Fix plpgsql failure in one case where a composite column is set to NULL (Tom) Fix possible failure when calling PL/Perl functions from PL/PerlU or vice versa (Tim Bunce) Add volatile markings in PL/Python to avoid possible compiler-specific misbehavior (Zdenek Kotala) Ensure PL/Tcl initializes the Tcl interpreter fully (Tom) The only known symptom of this oversight is that the Tcl clock command misbehaves if using Tcl 8.5 or later. Prevent ExecutorEnd from being run on portals created within a failed transaction or subtransaction (Tom) This is known to cause issues when using contrib/auto_explain. Prevent crash in contrib/dblink when too many key columns are specified to a dblink_build_sql_* function (Rushabh Lathia, Joe Conway) Allow zero-dimensional arrays in contrib/ltree operations (Tom) This case was formerly rejected as an error, but it's more convenient to treat it the same as a zero-element array. In particular this avoids unnecessary failures when an ltree operation is applied to the result of ARRAY(SELECT ...) and the sub-select returns no rows. Fix assorted crashes in contrib/xml2 caused by sloppy memory management (Tom) Make building of contrib/xml2 more robust on Windows (Andrew) Fix race condition in Windows signal handling (Radu Ilie) One known symptom of this bug is that rows in pg_listener could be dropped under heavy load. Make the configure script report failure if the C compiler does not provide a working 64-bit integer datatype (Tom) This case has been broken for some time, and no longer seems worth supporting, so just reject it at configure time instead. Update time zone data files to tzdata release 2010e for DST law changes in Bangladesh, Chile, Fiji, Mexico, Paraguay, Samoa. 2009-12-14 This release contains a variety of fixes from 8.4.1. For information about new features in the 8.4 major release, see . A dump/restore is not required for those running 8.4.X. However, if you have any hash indexes, you should REINDEX them after updating to 8.4.2, to repair possible damage. Protect against indirect security threats caused by index functions changing session-local state (Gurjeet Singh, Tom) This change prevents allegedly-immutable index functions from possibly subverting a superuser's session (CVE-2009-4136). Reject SSL certificates containing an embedded null byte in the common name (CN) field (Magnus) This prevents unintended matching of a certificate to a server or client name during SSL validation (CVE-2009-4034). Fix hash index corruption (Tom) The 8.4 change that made hash indexes keep entries sorted by hash value failed to update the bucket splitting and compaction routines to preserve the ordering. So application of either of those operations could lead to permanent corruption of an index, in the sense that searches might fail to find entries that are present. To deal with this, it is recommended to REINDEX any hash indexes you may have after installing this update. Fix possible crash during backend-startup-time cache initialization (Tom) Avoid crash on empty thesaurus dictionary (Tom) Prevent signals from interrupting VACUUM at unsafe times (Alvaro) This fix prevents a PANIC if a VACUUM FULL is cancelled after it's already committed its tuple movements, as well as transient errors if a plain VACUUM is interrupted after having truncated the table. Fix possible crash due to integer overflow in hash table size calculation (Tom) This could occur with extremely large planner estimates for the size of a hashjoin's result. Fix crash if a DROP is attempted on an internally-dependent object (Tom) Fix very rare crash in inet/cidr comparisons (Chris Mikkelson) Ensure that shared tuple-level locks held by prepared transactions are not ignored (Heikki) Fix premature drop of temporary files used for a cursor that is accessed within a subtransaction (Heikki) Fix memory leak in syslogger process when rotating to a new CSV logfile (Tom) Fix memory leak in postmaster when re-parsing pg_hba.conf (Tom) Fix Windows permission-downgrade logic (Jesse Morris) This fixes some cases where the database failed to start on Windows, often with misleading error messages such as could not locate matching postgres executable. Make FOR UPDATE/SHARE in the primary query not propagate into WITH queries (Tom) For example, in WITH w AS (SELECT * FROM foo) SELECT * FROM w, bar ... FOR UPDATE the FOR UPDATE will now affect bar but not foo. This is more useful and consistent than the original 8.4 behavior, which tried to propagate FOR UPDATE into the WITH query but always failed due to assorted implementation restrictions. It also follows the design rule that WITH queries are executed as if independent of the main query. Fix bug with a WITH RECURSIVE query immediately inside another one (Tom) Fix concurrency bug in hash indexes (Tom) Concurrent insertions could cause index scans to transiently report wrong results. Fix incorrect logic for GiST index page splits, when the split depends on a non-first column of the index (Paul Ramsey) Fix wrong search results for a multi-column GIN index with fastupdate enabled (Teodor) Fix bugs in WAL entry creation for GIN indexes (Tom) These bugs were masked when full_page_writes was on, but with it off a WAL replay failure was certain if a crash occurred before the next checkpoint. Don't error out if recycling or removing an old WAL file fails at the end of checkpoint (Heikki) It's better to treat the problem as non-fatal and allow the checkpoint to complete. Future checkpoints will retry the removal. Such problems are not expected in normal operation, but have been seen to be caused by misdesigned Windows anti-virus and backup software. Ensure WAL files aren't repeatedly archived on Windows (Heikki) This is another symptom that could happen if some other process interfered with deletion of a no-longer-needed file. Fix PAM password processing to be more robust (Tom) The previous code is known to fail with the combination of the Linux pam_krb5 PAM module with Microsoft Active Directory as the domain controller. It might have problems elsewhere too, since it was making unjustified assumptions about what arguments the PAM stack would pass to it. Raise the maximum authentication token (Kerberos ticket) size in GSSAPI and SSPI authentication methods (Ian Turner) While the old 2000-byte limit was more than enough for Unix Kerberos implementations, tickets issued by Windows Domain Controllers can be much larger. Ensure that domain constraints are enforced in constructs like ARRAY[...]::domain, where the domain is over an array type (Heikki) Fix foreign-key logic for some cases involving composite-type columns as foreign keys (Tom) Ensure that a cursor's snapshot is not modified after it is created (Alvaro) This could lead to a cursor delivering wrong results if later operations in the same transaction modify the data the cursor is supposed to return. Fix CREATE TABLE to properly merge default expressions coming from different inheritance parent tables (Tom) This used to work but was broken in 8.4. Re-enable collection of access statistics for sequences (Akira Kurosawa) This used to work but was broken in 8.3. Fix processing of ownership dependencies during CREATE OR REPLACE FUNCTION (Tom) Fix incorrect handling of WHERE x=x conditions (Tom) In some cases these could get ignored as redundant, but they aren't — they're equivalent to x IS NOT NULL. Fix incorrect plan construction when using hash aggregation to implement DISTINCT for textually identical volatile expressions (Tom) Fix Assert failure for a volatile SELECT DISTINCT ON expression (Tom) Fix ts_stat() to not fail on an empty tsvector value (Tom) Make text search parser accept underscores in XML attributes (Peter) Fix encoding handling in xml binary input (Heikki) If the XML header doesn't specify an encoding, we now assume UTF-8 by default; the previous handling was inconsistent. Fix bug with calling plperl from plperlu or vice versa (Tom) An error exit from the inner function could result in crashes due to failure to re-select the correct Perl interpreter for the outer function. Fix session-lifespan memory leak when a PL/Perl function is redefined (Tom) Ensure that Perl arrays are properly converted to PostgreSQL arrays when returned by a set-returning PL/Perl function (Andrew Dunstan, Abhijit Menon-Sen) This worked correctly already for non-set-returning functions. Fix rare crash in exception processing in PL/Python (Peter) Fix ecpg problem with comments in DECLARE CURSOR statements (Michael) Fix ecpg to not treat recently-added keywords as reserved words (Tom) This affected the keywords CALLED, CATALOG, DEFINER, ENUM, FOLLOWING, INVOKER, OPTIONS, PARTITION, PRECEDING, RANGE, SECURITY, SERVER, UNBOUNDED, and WRAPPER. Re-allow regular expression special characters in psql's \df function name parameter (Tom) In contrib/fuzzystrmatch, correct the calculation of levenshtein distances with non-default costs (Marcin Mank) In contrib/pg_standby, disable triggering failover with a signal on Windows (Fujii Masao) This never did anything useful, because Windows doesn't have Unix-style signals, but recent changes made it actually crash. Put FREEZE and VERBOSE options in the right order in the VACUUM command that contrib/vacuumdb produces (Heikki) Fix possible leak of connections when contrib/dblink encounters an error (Tatsuhito Kasahara) Ensure psql's flex module is compiled with the correct system header definitions (Tom) This fixes build failures on platforms where --enable-largefile causes incompatible changes in the generated code. Make the postmaster ignore any application_name parameter in connection request packets, to improve compatibility with future libpq versions (Tom) Update the timezone abbreviation files to match current reality (Joachim Wieland) This includes adding IDT to the default timezone abbreviation set. Update time zone data files to tzdata release 2009s for DST law changes in Antarctica, Argentina, Bangladesh, Fiji, Novokuznetsk, Pakistan, Palestine, Samoa, Syria; also historical corrections for Hong Kong. 2009-09-09 This release contains a variety of fixes from 8.4. For information about new features in the 8.4 major release, see . A dump/restore is not required for those running 8.4.X. Fix WAL page header initialization at the end of archive recovery (Heikki) This could lead to failure to process the WAL in a subsequent archive recovery. Fix cannot make new WAL entries during recovery error (Tom) Fix problem that could make expired rows visible after a crash (Tom) This bug involved a page status bit potentially not being set correctly after a server crash. Disallow RESET ROLE and RESET SESSION AUTHORIZATION inside security-definer functions (Tom, Heikki) This covers a case that was missed in the previous patch that disallowed SET ROLE and SET SESSION AUTHORIZATION inside security-definer functions. (See CVE-2007-6600) Make LOAD of an already-loaded loadable module into a no-op (Tom) Formerly, LOAD would attempt to unload and re-load the module, but this is unsafe and not all that useful. Make window function PARTITION BY and ORDER BY items always be interpreted as simple expressions (Tom) In 8.4.0 these lists were parsed following the rules used for top-level GROUP BY and ORDER BY lists. But this was not correct per the SQL standard, and it led to possible circularity. Fix several errors in planning of semi-joins (Tom) These led to wrong query results in some cases where IN or EXISTS was used together with another join. Fix handling of whole-row references to subqueries that are within an outer join (Tom) An example is SELECT COUNT(ss.*) FROM ... LEFT JOIN (SELECT ...) ss ON .... Here, ss.* would be treated as ROW(NULL,NULL,...) for null-extended join rows, which is not the same as a simple NULL. Now it is treated as a simple NULL. Fix Windows shared-memory allocation code (Tsutomu Yamada, Magnus) This bug led to the often-reported could not reattach to shared memory error message. Fix locale handling with plperl (Heikki) This bug could cause the server's locale setting to change when a plperl function is called, leading to data corruption. Fix handling of reloptions to ensure setting one option doesn't force default values for others (Itagaki Takahiro) Ensure that a fast shutdown request will forcibly terminate open sessions, even if a smart shutdown was already in progress (Fujii Masao) Avoid memory leak for array_agg() in GROUP BY queries (Tom) Treat to_char(..., 'TH') as an uppercase ordinal suffix with 'HH'/'HH12' (Heikki) It was previously handled as 'th' (lowercase). Include the fractional part in the result of EXTRACT(second) and EXTRACT(milliseconds) for time and time with time zone inputs (Tom) This has always worked for floating-point datetime configurations, but was broken in the integer datetime code. Fix overflow for INTERVAL 'x ms' when x is more than 2 million and integer datetimes are in use (Alex Hunsaker) Improve performance when processing toasted values in index scans (Tom) This is particularly useful for PostGIS. Fix a typo that disabled commit_delay (Jeff Janes) Output early-startup messages to postmaster.log if the server is started in silent mode (Tom) Previously such error messages were discarded, leading to difficulty in debugging. Remove translated FAQs (Peter) They are now on the wiki. The main FAQ was moved to the wiki some time ago. Fix pg_ctl to not go into an infinite loop if postgresql.conf is empty (Jeff Davis) Fix several errors in pg_dump's --binary-upgrade mode (Bruce, Tom) pg_dump --binary-upgrade is used by pg_migrator. Fix contrib/xml2's xslt_process() to properly handle the maximum number of parameters (twenty) (Tom) Improve robustness of libpq's code to recover from errors during COPY FROM STDIN (Tom) Avoid including conflicting readline and editline header files when both libraries are installed (Zdenek Kotala) Work around gcc bug that causes floating-point exception instead of division by zero on some platforms (Tom) Update time zone data files to tzdata release 2009l for DST law changes in Bangladesh, Egypt, Mauritius. 2009-07-01 After many years of development, PostgreSQL has become feature-complete in many areas. This release shows a targeted approach to adding features (e.g., authentication, monitoring, space reuse), and adds capabilities defined in the later SQL standards. The major areas of enhancement are: Windowing Functions Common Table Expressions and Recursive Queries Default and variadic parameters for functions Parallel Restore Column Permissions Per-database locale settings Improved hash indexes Improved join performance for EXISTS and NOT EXISTS queries Easier-to-use Warm Standby Automatic sizing of the Free Space Map Visibility Map (greatly reduces vacuum overhead for slowly-changing tables) Version-aware psql (backslash commands work against older servers) Support SSL certificates for user authentication Per-function runtime statistics Easy editing of functions in psql New contrib modules: pg_stat_statements, auto_explain, citext, btree_gin The above items are explained in more detail in the sections below. A dump/restore using pg_dump is required for those wishing to migrate data from any previous release. Observe the following incompatibilities: Use 64-bit integer datetimes by default (Neil Conway) Previously this was selected by configure's --enable-integer-datetimes option. To retain the old behavior, build with --disable-integer-datetimes. Remove ipcclean utility command (Bruce) The utility only worked on a few platforms. Users should use their operating system tools instead. Change default setting for log_min_messages to warning (previously it was notice) to reduce log file volume (Tom) Change default setting for max_prepared_transactions to zero (previously it was 5) (Tom) Make debug_print_parse, debug_print_rewritten, and debug_print_plan output appear at LOG message level, not DEBUG1 as formerly (Tom) Make debug_pretty_print default to on (Tom) Remove explain_pretty_print parameter (no longer needed) (Tom) Make log_temp_files settable by superusers only, like other logging options (Simon Riggs) Remove automatic appending of the epoch timestamp when no % escapes are present in log_filename (Robert Haas) This change was made because some users wanted a fixed log filename, for use with an external log rotation tool. Remove log_restartpoints from recovery.conf; instead use log_checkpoints (Simon) Remove krb_realm and krb_server_hostname; these are now set in pg_hba.conf instead (Magnus) There are also significant changes in pg_hba.conf, as described below. Change TRUNCATE and LOCK to apply to child tables of the specified table(s) (Peter) These commands now accept an ONLY option that prevents processing child tables; this option must be used if the old behavior is needed. SELECT DISTINCT and UNION/INTERSECT/EXCEPT no longer always produce sorted output (Tom) Previously, these types of queries always removed duplicate rows by means of Sort/Unique processing (i.e., sort then remove adjacent duplicates). Now they can be implemented by hashing, which will not produce sorted output. If an application relied on the output being in sorted order, the recommended fix is to add an ORDER BY clause. As a short-term workaround, the previous behavior can be restored by disabling enable_hashagg, but that is a very performance-expensive fix. SELECT DISTINCT ON never uses hashing, however, so its behavior is unchanged. Force child tables to inherit CHECK constraints from parents (Alex Hunsaker, Nikhil Sontakke, Tom) Formerly it was possible to drop such a constraint from a child table, allowing rows that violate the constraint to be visible when scanning the parent table. This was deemed inconsistent, as well as contrary to SQL standard. Disallow negative LIMIT or OFFSET values, rather than treating them as zero (Simon) Disallow LOCK TABLE outside a transaction block (Tom) Such an operation is useless because the lock would be released immediately. Sequences now contain an additional start_value column (Zoltan Boszormenyi) This supports ALTER SEQUENCE ... RESTART. Make numeric zero raised to a fractional power return 0, rather than throwing an error, and make numeric zero raised to the zero power return 1, rather than error (Bruce) This matches the longstanding float8 behavior. Allow unary minus of floating-point values to produce minus zero (Tom) The changed behavior is more IEEE-standard compliant. Throw an error if an escape character is the last character in a LIKE pattern (i.e., it has nothing to escape) (Tom) Previously, such an escape character was silently ignored, thus possibly masking application logic errors. Remove ~=~ and ~<>~ operators formerly used for LIKE index comparisons (Tom) Pattern indexes now use the regular equality operator. xpath() now passes its arguments to libxml without any changes (Andrew) This means that the XML argument must be a well-formed XML document. The previous coding attempted to allow XML fragments, but it did not work well. Make xmlelement() format attribute values just like content values (Peter) Previously, attribute values were formatted according to the normal SQL output behavior, which is sometimes at odds with XML rules. Rewrite memory management for libxml-using functions (Tom) This change should avoid some compatibility problems with use of libxml in PL/Perl and other add-on code. Adopt a faster algorithm for hash functions (Kenneth Marshall, based on work of Bob Jenkins) Many of the built-in hash functions now deliver different results on little-endian and big-endian platforms. DateStyle no longer controls interval output formatting; instead there is a new variable IntervalStyle (Ron Mayer) Improve consistency of handling of fractional seconds in timestamp and interval output (Ron Mayer) This may result in displaying a different number of fractional digits than before, or rounding instead of truncating. Make to_char()'s localized month/day names depend on LC_TIME, not LC_MESSAGES (Euler Taveira de Oliveira) Cause to_date() and to_timestamp() to more consistently report errors for invalid input (Brendan Jurd) Previous versions would often ignore or silently misread input that did not match the format string. Such cases will now result in an error. Fix to_timestamp() to not require upper/lower case matching for meridian (AM/PM) and era (BC/AD) format designations (Brendan Jurd) For example, input value ad now matches the format string AD. Below you will find a detailed account of the changes between PostgreSQL 8.4 and the previous major release. Improve optimizer statistics calculations (Jan Urbanski, Tom) In particular, estimates for full-text-search operators are greatly improved. Allow SELECT DISTINCT and UNION/INTERSECT/EXCEPT to use hashing (Tom) This means that these types of queries no longer automatically produce sorted output. Create explicit concepts of semi-joins and anti-joins (Tom) This work formalizes our previous ad-hoc treatment of IN (SELECT ...) clauses, and extends it to EXISTS and NOT EXISTS clauses. It should result in significantly better planning of EXISTS and NOT EXISTS queries. In general, logically equivalent IN and EXISTS clauses should now have similar performance, whereas previously IN often won. Improve optimization of sub-selects beneath outer joins (Tom) Formerly, a sub-select or view could not be optimized very well if it appeared within the nullable side of an outer join and contained non-strict expressions (for instance, constants) in its result list. Improve the performance of text_position() and related functions by using Boyer-Moore-Horspool searching (David Rowley) This is particularly helpful for long search patterns. Reduce I/O load of writing the statistics collection file by writing the file only when requested (Martin Pihlak) Improve performance for bulk inserts (Robert Haas, Simon) Increase the default value of default_statistics_target from 10 to 100 (Greg Sabino Mullane, Tom) The maximum value was also increased from 1000 to 10000. Perform constraint_exclusion checking by default in queries involving inheritance or UNION ALL (Tom) A new constraint_exclusion setting, partition, was added to specify this behavior. Allow I/O read-ahead for bitmap index scans (Greg Stark) The amount of read-ahead is controlled by effective_io_concurrency. This feature is available only if the kernel has posix_fadvise() support. Inline simple set-returning SQL functions in FROM clauses (Richard Rowell) Improve performance of multi-batch hash joins by providing a special case for join key values that are especially common in the outer relation (Bryce Cutt, Ramon Lawrence) Reduce volume of temporary data in multi-batch hash joins by suppressing physical tlist optimization (Michael Henderson, Ramon Lawrence) Avoid waiting for idle-in-transaction sessions during CREATE INDEX CONCURRENTLY (Simon) Improve performance of shared cache invalidation (Tom) Convert many postgresql.conf settings to enumerated values so that pg_settings can display the valid values (Magnus) Add cursor_tuple_fraction parameter to control the fraction of a cursor's rows that the planner assumes will be fetched (Robert Hell) Allow underscores in the names of custom variable classes in postgresql.conf (Tom) Remove support for the (insecure) crypt authentication method (Magnus) This effectively obsoletes pre-PostgreSQL 7.2 client libraries, as there is no longer any non-plaintext password method that they can use. Support regular expressions in pg_ident.conf (Magnus) Allow Kerberos/GSSAPI parameters to be changed without restarting the postmaster (Magnus) Support SSL certificate chains in server certificate file (Andrew Gierth) Including the full certificate chain makes the client able to verify the certificate without having all intermediate CA certificates present in the local store, which is often the case for commercial CAs. Report appropriate error message for combination of MD5 authentication and db_user_namespace enabled (Bruce) Change all authentication options to use name=value syntax (Magnus) This makes incompatible changes to the ldap, pam and ident authentication methods. All pg_hba.conf entries with these methods need to be rewritten using the new format. Remove the ident sameuser option, instead making that behavior the default if no usermap is specified (Magnus) Allow a usermap parameter for all external authentication methods (Magnus) Previously a usermap was only supported for ident authentication. Add clientcert option to control requesting of a client certificate (Magnus) Previously this was controlled by the presence of a root certificate file in the server's data directory. Add cert authentication method to allow user authentication via SSL certificates (Magnus) Previously SSL certificates could only verify that the client had access to a certificate, not authenticate a user. Allow krb5, gssapi and sspi realm and krb5 host settings to be specified in pg_hba.conf (Magnus) These override the settings in postgresql.conf. Add include_realm parameter for krb5, gssapi, and sspi methods (Magnus) This allows identical usernames from different realms to be authenticated as different database users using usermaps. Parse pg_hba.conf fully when it is loaded, so that errors are reported immediately (Magnus) Previously, most errors in the file wouldn't be detected until clients tried to connect, so an erroneous file could render the system unusable. With the new behavior, if an error is detected during reload then the bad file is rejected and the postmaster continues to use its old copy. Show all parsing errors in pg_hba.conf instead of aborting after the first one (Selena Deckelmann) Support ident authentication over Unix-domain sockets on Solaris (Garick Hamlin) Provide an option to pg_start_backup() to force its implied checkpoint to finish as quickly as possible (Tom) The default behavior avoids excess I/O consumption, but that is pointless if no concurrent query activity is going on. Make pg_stop_backup() wait for modified WAL files to be archived (Simon) This guarantees that the backup is valid at the time pg_stop_backup() completes. When archiving is enabled, rotate the last WAL segment at shutdown so that all transactions can be archived immediately (Guillaume Smet, Heikki) Delay smart shutdown while a continuous archiving base backup is in progress (Laurenz Albe) Cancel a continuous archiving base backup if fast shutdown is requested (Laurenz Albe) Allow recovery.conf boolean variables to take the same range of string values as postgresql.conf boolean variables (Bruce) Add pg_conf_load_time() to report when the PostgreSQL configuration files were last loaded (George Gensure) Add pg_terminate_backend() to safely terminate a backend (the SIGTERM signal works also) (Tom, Bruce) While it's always been possible to SIGTERM a single backend, this was previously considered unsupported; and testing of the case found some bugs that are now fixed. Add ability to track user-defined functions' call counts and runtimes (Martin Pihlak) Function statistics appear in a new system view, pg_stat_user_functions. Tracking is controlled by the new parameter track_functions. Allow specification of the maximum query string size in pg_stat_activity via new track_activity_query_size parameter (Thomas Lee) Increase the maximum line length sent to syslog, in hopes of improving performance (Tom) Add read-only configuration variables segment_size, wal_block_size, and wal_segment_size (Bernd Helmle) When reporting a deadlock, report the text of all queries involved in the deadlock to the server log (Itagaki Takahiro) Add pg_stat_get_activity(pid) function to return information about a specific process id (Magnus) Allow the location of the server's statistics file to be specified via stats_temp_directory (Magnus) This allows the statistics file to be placed in a RAM-resident directory to reduce I/O requirements. On startup/shutdown, the file is copied to its traditional location ($PGDATA/global/) so it is preserved across restarts. Add support for WINDOW functions (Hitoshi Harada) Add support for WITH clauses (CTEs), including WITH RECURSIVE (Yoshiyuki Asaba, Tatsuo Ishii, Tom) Add TABLE command (Peter) TABLE tablename is a SQL standard short-hand for SELECT * FROM tablename. Allow AS to be optional when specifying a SELECT (or RETURNING) column output label (Hiroshi Saito) This works so long as the column label is not any PostgreSQL keyword; otherwise AS is still needed. Support set-returning functions in SELECT result lists even for functions that return their result via a tuplestore (Tom) In particular, this means that functions written in PL/pgSQL and other PL languages can now be called this way. Support set-returning functions in the output of aggregation and grouping queries (Tom) Allow SELECT FOR UPDATE/SHARE to work on inheritance trees (Tom) Add infrastructure for SQL/MED (Martin Pihlak, Peter) There are no remote or external SQL/MED capabilities yet, but this change provides a standardized and future-proof system for managing connection information for modules like dblink and plproxy. Invalidate cached plans when referenced schemas, functions, operators, or operator classes are modified (Martin Pihlak, Tom) This improves the system's ability to respond to on-the-fly DDL changes. Allow comparison of composite types and allow arrays of anonymous composite types (Tom) This allows constructs such as row(1, 1.1) = any (array[row(7, 7.7), row(1, 1.0)]). This is particularly useful in recursive queries. Add support for Unicode string literal and identifier specifications using code points, e.g. U&'d\0061t\+000061' (Peter) Reject \000 in string literals and COPY data (Tom) Previously, this was accepted but had the effect of terminating the string contents. Improve the parser's ability to report error locations (Tom) An error location is now reported for many semantic errors, such as mismatched datatypes, that previously could not be localized. Support statement-level ON TRUNCATE triggers (Simon) Add RESTART/CONTINUE IDENTITY options for TRUNCATE TABLE (Zoltan Boszormenyi) The start value of a sequence can be changed by ALTER SEQUENCE START WITH. Allow TRUNCATE tab1, tab1 to succeed (Bruce) Add a separate TRUNCATE permission (Robert Haas) Make EXPLAIN VERBOSE show the output columns of each plan node (Tom) Previously EXPLAIN VERBOSE output an internal representation of the query plan. (That behavior is now available via debug_print_plan.) Make EXPLAIN identify subplans and initplans with individual labels (Tom) Make EXPLAIN honor debug_print_plan (Tom) Allow EXPLAIN on CREATE TABLE AS (Peter) Allow sub-selects in LIMIT and OFFSET (Tom) Add SQL-standard syntax for LIMIT/OFFSET capabilities (Peter) To wit, OFFSET num {ROW|ROWS} FETCH {FIRST|NEXT} [num] {ROW|ROWS} ONLY. Add support for column-level privileges (Stephen Frost, KaiGai Kohei) Refactor multi-object DROP operations to reduce the need for CASCADE (Alex Hunsaker) For example, if table B has a dependency on table A, the command DROP TABLE A, B no longer requires the CASCADE option. Fix various problems with concurrent DROP commands by ensuring that locks are taken before we begin to drop dependencies of an object (Tom) Improve reporting of dependencies during DROP commands (Tom) Add WITH [NO] DATA clause to CREATE TABLE AS, per the SQL standard (Peter, Tom) Add support for user-defined I/O conversion casts (Heikki) Allow CREATE AGGREGATE to use an internal transition datatype (Tom) Add LIKE clause to CREATE TYPE (Tom) This simplifies creation of data types that use the same internal representation as an existing type. Allow specification of the type category and preferred status for user-defined base types (Tom) This allows more control over the coercion behavior of user-defined types. Allow CREATE OR REPLACE VIEW to add columns to the end of a view (Robert Haas) Add ALTER TYPE RENAME (Petr Jelinek) Add ALTER SEQUENCE ... RESTART (with no parameter) to reset a sequence to its initial value (Zoltan Boszormenyi) Modify the ALTER TABLE syntax to allow all reasonable combinations for tables, indexes, sequences, and views (Tom) This change allows the following new syntaxes: ALTER SEQUENCE OWNER TO ALTER VIEW ALTER COLUMN SET/DROP DEFAULT ALTER VIEW OWNER TO ALTER VIEW SET SCHEMA There is no actual new functionality here, but formerly you had to say ALTER TABLE to do these things, which was confusing. Add support for the syntax ALTER TABLE ... ALTER COLUMN ... SET DATA TYPE (Peter) This is SQL-standard syntax for functionality that was already supported. Make ALTER TABLE SET WITHOUT OIDS rewrite the table to physically remove OID values (Tom) Also, add ALTER TABLE SET WITH OIDS to rewrite the table to add OIDs. Improve reporting of CREATE/DROP/RENAME DATABASE failure when uncommitted prepared transactions are the cause (Tom) Make LC_COLLATE and LC_CTYPE into per-database settings (Radek Strnad, Heikki) This makes collation similar to encoding, which was always configurable per database. Improve checks that the database encoding, collation (LC_COLLATE), and character classes (LC_CTYPE) match (Heikki, Tom) Note in particular that a new database's encoding and locale settings can be changed only when copying from template0. This prevents possibly copying data that doesn't match the settings. Add ALTER DATABASE SET TABLESPACE to move a database to a new tablespace (Guillaume Lelarge, Bernd Helmle) Add a VERBOSE option to the CLUSTER command and clusterdb (Jim Cox) Decrease memory requirements for recording pending trigger events (Tom) Dramatically improve the speed of building and accessing hash indexes (Tom Raney, Shreya Bhargava) This allows hash indexes to be sometimes faster than btree indexes. However, hash indexes are still not crash-safe. Make hash indexes store only the hash code, not the full value of the indexed column (Xiao Meng) This greatly reduces the size of hash indexes for long indexed values, improving performance. Implement fast update option for GIN indexes (Teodor, Oleg) This option greatly improves update speed at a small penalty in search speed. xxx_pattern_ops indexes can now be used for simple equality comparisons, not only for LIKE (Tom) Remove the requirement to use @@@ when doing GIN weighted lookups on full text indexes (Tom, Teodor) The normal @@ text search operator can be used instead. Add an optimizer selectivity function for @@ text search operations (Jan Urbanski) Allow prefix matching in full text searches (Teodor Sigaev, Oleg Bartunov) Support multi-column GIN indexes (Teodor Sigaev) Improve support for Nepali language and Devanagari alphabet (Teodor) Track free space in separate per-relation fork files (Heikki) Free space discovered by VACUUM is now recorded in *_fsm files, rather than in a fixed-sized shared memory area. The max_fsm_pages and max_fsm_relations settings have been removed, greatly simplifying administration of free space management. Add a visibility map to track pages that do not require vacuuming (Heikki) This allows VACUUM to avoid scanning all of a table when only a portion of the table needs vacuuming. The visibility map is stored in per-relation fork files. Add vacuum_freeze_table_age parameter to control when VACUUM should ignore the visibility map and do a full table scan to freeze tuples (Heikki) Track transaction snapshots more carefully (Alvaro) This improves VACUUM's ability to reclaim space in the presence of long-running transactions. Add ability to specify per-relation autovacuum and TOAST parameters in CREATE TABLE (Alvaro, Euler Taveira de Oliveira) Autovacuum options used to be stored in a system table. Add --freeze option to vacuumdb (Bruce) Add a CaseSensitive option for text search synonym dictionaries (Simon) Improve the precision of NUMERIC division (Tom) Add basic arithmetic operators for int2 with int8 (Tom) This eliminates the need for explicit casting in some situations. Allow UUID input to accept an optional hyphen after every fourth digit (Robert Haas) Allow on/off as input for the boolean data type (Itagaki Takahiro) Allow spaces around NaN in the input string for type numeric (Sam Mason) Reject year 0 BC and years 000 and 0000 (Tom) Previously these were interpreted as 1 BC. (Note: years 0 and 00 are still assumed to be the year 2000.) Include SGT (Singapore time) in the default list of known time zone abbreviations (Tom) Support infinity and -infinity as values of type date (Tom) Make parsing of interval literals more standard-compliant (Tom, Ron Mayer) For example, INTERVAL '1' YEAR now does what it's supposed to. Allow interval fractional-seconds precision to be specified after the second keyword, for SQL standard compliance (Tom) Formerly the precision had to be specified after the keyword interval. (For backwards compatibility, this syntax is still supported, though deprecated.) Data type definitions will now be output using the standard format. Support the IS0 8601 interval syntax (Ron Mayer, Kevin Grittner) For example, INTERVAL 'P1Y2M3DT4H5M6.7S' is now supported. Add IntervalStyle parameter which controls how interval values are output (Ron Mayer) Valid values are: postgres, postgres_verbose, sql_standard, iso_8601. This setting also controls the handling of negative interval input when only some fields have positive/negative designations. Improve consistency of handling of fractional seconds in timestamp and interval output (Ron Mayer) Improve the handling of casts applied to ARRAY[] constructs, such as ARRAY[...]::integer[] (Brendan Jurd) Formerly PostgreSQL attempted to determine a data type for the ARRAY[] construct without reference to the ensuing cast. This could fail unnecessarily in many cases, in particular when the ARRAY[] construct was empty or contained only ambiguous entries such as NULL. Now the cast is consulted to determine the type that the array elements must be. Make SQL-syntax ARRAY dimensions optional to match the SQL standard (Peter) Add array_ndims() to return the number of dimensions of an array (Robert Haas) Add array_length() to return the length of an array for a specified dimension (Jim Nasby, Robert Haas, Peter Eisentraut) Add aggregate function array_agg(), which returns all aggregated values as a single array (Robert Haas, Jeff Davis, Peter) Add unnest(), which converts an array to individual row values (Tom) This is the opposite of array_agg(). Add array_fill() to create arrays initialized with a value (Pavel Stehule) Add generate_subscripts() to simplify generating the range of an array's subscripts (Pavel Stehule) Consider TOAST compression on values as short as 32 bytes (previously 256 bytes) (Greg Stark) Require 25% minimum space savings before using TOAST compression (previously 20% for small values and any-savings-at-all for large values) (Greg) Improve TOAST heuristics for rows that have a mix of large and small toastable fields, so that we prefer to push large values out of line and don't compress small values unnecessarily (Greg, Tom) Document that setseed() allows values from -1 to 1 (not just 0 to 1), and enforce the valid range (Kris Jurka) Add server-side function lo_import(filename, oid) (Tatsuo) Add quote_nullable(), which behaves like quote_literal() but returns the string NULL for a null argument (Brendan Jurd) Improve full text search headline() function to allow extracting several fragments of text (Sushant Sinha) Add suppress_redundant_updates_trigger() trigger function to avoid overhead for non-data-changing updates (Andrew) Add div(numeric, numeric) to perform numeric division without rounding (Tom) Add timestamp and timestamptz versions of generate_series() (Hitoshi Harada) Implement current_query() for use by functions that need to know the currently running query (Tomas Doran) Add pg_get_keywords() to return a list of the parser keywords (Dave Page) Add pg_get_functiondef() to see a function's definition (Abhijit Menon-Sen) Allow the second argument of pg_get_expr() to be zero when deparsing an expression that does not contain variables (Tom) Modify pg_relation_size() to use regclass (Heikki) pg_relation_size(data_type_name) no longer works. Add boot_val and reset_val columns to pg_settings output (Greg Smith) Add source file name and line number columns to pg_settings output for variables set in a configuration file (Magnus, Alvaro) For security reasons, these columns are only visible to superusers. Add support for CURRENT_CATALOG, CURRENT_SCHEMA, SET CATALOG, SET SCHEMA (Peter) These provide SQL-standard syntax for existing features. Add pg_typeof() which returns the data type of any value (Brendan Jurd) Make version() return information about whether the server is a 32- or 64-bit binary (Bruce) Fix the behavior of information schema columns is_insertable_into and is_updatable to be consistent (Peter) Improve the behavior of information schema datetime_precision columns (Peter) These columns now show zero for date columns, and 6 (the default precision) for time, timestamp, and interval without a declared precision, rather than showing null as formerly. Convert remaining builtin set-returning functions to use OUT parameters (Jaime Casanova) This makes it possible to call these functions without specifying a column list: pg_show_all_settings(), pg_lock_status(), pg_prepared_xact(), pg_prepared_statement(), pg_cursor() Make pg_*_is_visible() and has_*_privilege() functions return NULL for invalid OIDs, rather than reporting an error (Tom) Extend has_*_privilege() functions to allow inquiring about the OR of multiple privileges in one call (Stephen Frost, Tom) Add has_column_privilege() and has_any_column_privilege() functions (Stephen Frost, Tom) Support variadic functions (functions with a variable number of arguments) (Pavel Stehule) Only trailing arguments can be optional, and they all must be of the same data type. Support default values for function arguments (Pavel Stehule) Add CREATE FUNCTION ... RETURNS TABLE clause (Pavel Stehule) Allow SQL-language functions to return the output of an INSERT/UPDATE/DELETE RETURNING clause (Tom) Support EXECUTE USING for easier insertion of data values into a dynamic query string (Pavel Stehule) Allow looping over the results of a cursor using a FOR loop (Pavel Stehule) Support RETURN QUERY EXECUTE (Pavel Stehule) Improve the RAISE command (Pavel Stehule) Support DETAIL and HINT fields Support specification of the SQLSTATE error code Support an exception name parameter Allow RAISE without parameters in an exception block to re-throw the current error Allow specification of SQLSTATE codes in EXCEPTION lists (Pavel Stehule) This is useful for handling custom SQLSTATE codes. Support the CASE statement (Pavel Stehule) Make RETURN QUERY set the special FOUND and GET DIAGNOSTICS ROW_COUNT variables (Pavel Stehule) Make FETCH and MOVE set the GET DIAGNOSTICS ROW_COUNT variable (Andrew Gierth) Make EXIT without a label always exit the innermost loop (Tom) Formerly, if there were a BEGIN block more closely nested than any loop, it would exit that block instead. The new behavior matches Oracle(TM) and is also what was previously stated by our own documentation. Make processing of string literals and nested block comments match the main SQL parser's processing (Tom) In particular, the format string in RAISE now works the same as any other string literal, including being subject to standard_conforming_strings. This change also fixes other cases in which valid commands would fail when standard_conforming_strings is on. Avoid memory leakage when the same function is called at varying exception-block nesting depths (Tom) Fix pg_ctl restart to preserve command-line arguments (Bruce) Add -w/--no-password option that prevents password prompting in all utilities that have a -W/--password option (Peter) Remove -q (quiet) option of createdb, createuser, dropdb, dropuser (Peter) These options have had no effect since PostgreSQL 8.3. Remove verbose startup banner; now just suggest help (Joshua Drake) Make help show common backslash commands (Greg Sabino Mullane) Add \pset format wrapped mode to wrap output to the screen width, or file/pipe output too if \pset columns is set (Bryce Nesbitt) Allow all supported spellings of boolean values in \pset, rather than just on and off (Bruce) Formerly, any string other than off was silently taken to mean true. psql will now complain about unrecognized spellings (but still take them as true). Use the pager for wide output (Bruce) Require a space between a one-letter backslash command and its first argument (Bernd Helmle) This removes a historical source of ambiguity. Improve tab completion support for schema-qualified and quoted identifiers (Greg Sabino Mullane) Add optional on/off argument for \timing (David Fetter) Display access control rights on multiple lines (Brendan Jurd, Andreas Scherbaum) Make \l show database access privileges (Andrew Gilligan) Make \l+ show database sizes, if permissions allow (Andrew Gilligan) Add the \ef command to edit function definitions (Abhijit Menon-Sen) Make \d* commands that do not have a pattern argument show system objects only if the S modifier is specified (Greg Sabino Mullane, Bruce) The former behavior was inconsistent across different variants of \d, and in most cases it provided no easy way to see just user objects. Improve \d* commands to work with older PostgreSQL server versions (back to 7.4), not only the current server version (Guillaume Lelarge) Make \d show foreign-key constraints that reference the selected table (Kenneth D'Souza) Make \d on a sequence show its column values (Euler Taveira de Oliveira) Add column storage type and other relation options to the \d+ display (Gregory Stark, Euler Taveira de Oliveira) Show relation size in \dt+ output (Dickson S. Guedes) Show the possible values of enum types in \dT+ (David Fetter) Allow \dC to accept a wildcard pattern, which matches either datatype involved in the cast (Tom) Add a function type column to \df's output, and add options to list only selected types of functions (David Fetter) Make \df not hide functions that take or return type cstring (Tom) Previously, such functions were hidden because most of them are datatype I/O functions, which were deemed uninteresting. The new policy about hiding system functions by default makes this wart unnecessary. Add a --no-tablespaces option to pg_dump/pg_dumpall/pg_restore so that dumps can be restored to clusters that have non-matching tablespace layouts (Gavin Roy) Remove -d and -D options from pg_dump and pg_dumpall (Tom) These options were too frequently confused with the option to select a database name in other PostgreSQL client applications. The functionality is still available, but you must now spell out the long option name --inserts or --column-inserts. Remove -i/--ignore-version option from pg_dump and pg_dumpall (Tom) Use of this option does not throw an error, but it has no effect. This option was removed because the version checks are necessary for safety. Disable statement_timeout during dump and restore (Joshua Drake) Add pg_dump/pg_dumpall option --lock-wait-timeout (David Gould) This allows dumps to fail if unable to acquire a shared lock within the specified amount of time. Reorder pg_dump --data-only output to dump tables referenced by foreign keys before the referencing tables (Tom) This allows data loads when foreign keys are already present. If circular references make a safe ordering impossible, a NOTICE is issued. Allow pg_dump, pg_dumpall, and pg_restore to use a specified role (Benedek László) Allow pg_restore to use multiple concurrent connections to do the restore (Andrew) The number of concurrent connections is controlled by the option --jobs. This is supported only for custom-format archives. Allow the OID to be specified when importing a large object, via new function lo_import_with_oid() (Tatsuo) Add events support (Andrew Chernow, Merlin Moncure) This adds the ability to register callbacks to manage private data associated with PGconn and PGresult objects. Improve error handling to allow the return of multiple error messages as multi-line error reports (Magnus) Make PQexecParams() and related functions return PGRES_EMPTY_QUERY for an empty query (Tom) They previously returned PGRES_COMMAND_OK. Document how to avoid the overhead of WSACleanup() on Windows (Andrew Chernow) Do not rely on Kerberos tickets to determine the default database username (Magnus) Previously, a Kerberos-capable build of libpq would use the principal name from any available Kerberos ticket as default database username, even if the connection wasn't using Kerberos authentication. This was deemed inconsistent and confusing. The default username is now determined the same way with or without Kerberos. Note however that the database username must still match the ticket when Kerberos authentication is used. Fix certificate validation for SSL connections (Magnus) libpq now supports verifying both the certificate and the name of the server when making SSL connections. If a root certificate is not available to use for verification, SSL connections will fail. The sslmode parameter is used to enable certificate verification and set the level of checking. The default is still not to do any verification, allowing connections to SSL-enabled servers without requiring a root certificate on the client. Support wildcard server certificates (Magnus) If a certificate CN starts with *, it will be treated as a wildcard when matching the hostname, allowing the use of the same certificate for multiple servers. Allow the file locations for client certificates to be specified (Mark Woodward, Alvaro, Magnus) Add a PQinitOpenSSL function to allow greater control over OpenSSL/libcrypto initialization (Andrew Chernow) Make libpq unregister its OpenSSL callbacks when no database connections remain open (Bruce, Magnus, Russell Smith) This is required for applications that unload the libpq library, otherwise invalid OpenSSL callbacks will remain. Add localization support for messages (Euler Taveira de Oliveira) ecpg parser is now automatically generated from the server parser (Michael) Previously the ecpg parser was hand-maintained. Add support for single-use plans with out-of-line parameters (Tom) Add new SPI_OK_REWRITTEN return code for SPI_execute() (Heikki) This is used when a command is rewritten to another type of command. Remove unnecessary inclusions from executor/spi.h (Tom) SPI-using modules might need to add some #include lines if they were depending on spi.h to include things for them. Update build system to use Autoconf 2.61 (Peter) Require GNU bison for source code builds (Peter) This has effectively been required for several years, but now there is no infrastructure claiming to support other parser tools. Add pg_config --htmldir option (Peter) Pass float4 by value inside the server (Zoltan Boszormenyi) Add configure option --disable-float4-byval to use the old behavior. External C functions that use old-style (version 0) call convention and pass or return float4 values will be broken by this change, so you may need the configure option if you have such functions and don't want to update them. Pass float8, int8, and related datatypes by value inside the server on 64-bit platforms (Zoltan Boszormenyi) Add configure option --disable-float8-byval to use the old behavior. As above, this change might break old-style external C functions. Add configure options --with-segsize, --with-blocksize, --with-wal-blocksize, --with-wal-segsize (Zdenek Kotala, Tom) This simplifies build-time control over several constants that previously could only be changed by editing pg_config_manual.h. Allow threaded builds on Solaris 2.5 (Bruce) Use the system's getopt_long() on Solaris (Zdenek Kotala, Tom) This makes option processing more consistent with what Solaris users expect. Add support for the Sun Studio compiler on Linux (Julius Stroffek) Append the major version number to the backend gettext domain, and the soname major version number to libraries' gettext domain (Peter) This simplifies parallel installations of multiple versions. Add support for code coverage testing with gcov (Michelle Caisse) Allow out-of-tree builds on Mingw and Cygwin (Richard Evans) Fix the use of Mingw as a cross-compiling source platform (Peter) Support 64-bit time zone data files (Heikki) This adds support for daylight saving time (DST) calculations beyond the year 2038. Deprecate use of platform's time_t data type (Tom) Some platforms have migrated to 64-bit time_t, some have not, and Windows can't make up its mind what it's doing. Define pg_time_t to have the same meaning as time_t, but always be 64 bits (unless the platform has no 64-bit integer type), and use that type in all module APIs and on-disk data formats. Fix bug in handling of the time zone database when cross-compiling (Richard Evans) Link backend object files in one step, rather than in stages (Peter) Improve gettext support to allow better translation of plurals (Peter) Add message translation support to the PL languages (Alvaro, Peter) Add more DTrace probes (Robert Lor) Enable DTrace support on Mac OS X Leopard and other non-Solaris platforms (Robert Lor) Simplify and standardize conversions between C strings and text datums, by providing common functions for the purpose (Brendan Jurd, Tom) Clean up the include/catalog/ header files so that frontend programs can include them without including postgres.h (Zdenek Kotala) Make name char-aligned, and suppress zero-padding of name entries in indexes (Tom) Recover better if dynamically-loaded code executes exit() (Tom) Add a hook to let plug-ins monitor the executor (Itagaki Takahiro) Add a hook to allow the planner's statistics lookup behavior to be overridden (Simon Riggs) Add shmem_startup_hook() for custom shared memory requirements (Tom) Replace the index access method amgetmulti entry point with amgetbitmap, and extend the API for amgettuple to support run-time determination of operator lossiness (Heikki, Tom, Teodor) The API for GIN and GiST opclass consistent functions has been extended as well. Add support for partial-match searches in GIN indexes (Teodor Sigaev, Oleg Bartunov) Replace pg_class column reltriggers with boolean relhastriggers (Simon) Also remove unused pg_class columns relukeys, relfkeys, and relrefs. Add a relistemp column to pg_class to ease identification of temporary tables (Tom) Move platform FAQs into the main documentation (Peter) Prevent parser input files from being built with any conflicts (Peter) Add support for the KOI8U (Ukrainian) encoding (Peter) Add Japanese message translations (Japan PostgreSQL Users Group) This used to be maintained as a separate project. Fix problem when setting LC_MESSAGES on MSVC-built systems (Hiroshi Inoue, Hiroshi Saito, Magnus) Add contrib/auto_explain to automatically run EXPLAIN on queries exceeding a specified duration (Itagaki Takahiro, Tom) Add contrib/btree_gin to allow GIN indexes to handle more datatypes (Oleg, Teodor) Add contrib/citext to provide a case-insensitive, multibyte-aware text data type (David Wheeler) Add contrib/pg_stat_statements for server-wide tracking of statement execution statistics (Itagaki Takahiro) Add duration and query mode options to contrib/pgbench (Itagaki Takahiro) Make contrib/pgbench use table names pgbench_accounts, pgbench_branches, pgbench_history, and pgbench_tellers, rather than just accounts, branches, history, and tellers (Tom) This is to reduce the risk of accidentally destroying real data by running pgbench. Fix contrib/pgstattuple to handle tables and indexes with over 2 billion pages (Tatsuhito Kasahara) In contrib/fuzzystrmatch, add a version of the Levenshtein string-distance function that allows the user to specify the costs of insertion, deletion, and substitution (Volkan Yazici) Make contrib/ltree support multibyte encodings (laser) Enable contrib/dblink to use connection information stored in the SQL/MED catalogs (Joe Conway) Improve contrib/dblink's reporting of errors from the remote server (Joe Conway) Make contrib/dblink set client_encoding to match the local database's encoding (Joe Conway) This prevents encoding problems when communicating with a remote database that uses a different encoding. Make sure contrib/dblink uses a password supplied by the user, and not accidentally taken from the server's .pgpass file (Joe Conway) This is a minor security enhancement. Add fsm_page_contents() to contrib/pageinspect (Heikki) Modify get_raw_page() to support free space map (*_fsm) files. Also update contrib/pg_freespacemap. Add support for multibyte encodings to contrib/pg_trgm (Teodor) Rewrite contrib/intagg to use new functions array_agg() and unnest() (Tom) Make contrib/pg_standby recover all available WAL before failover (Fujii Masao, Simon, Heikki) To make this work safely, you now need to set the new recovery_end_command option in recovery.conf to clean up the trigger file after failover. pg_standby will no longer remove the trigger file itself. contrib/pg_standby's -l option is now a no-op, because it is unsafe to use a symlink (Simon)