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4 <sect1 id="release-8-4">
5 <title>Release 8.4</title>
8 <title>Release date</title>
9 <simpara>2009-07-01</simpara>
13 <title>Overview</title>
16 After many years of development, <productname>PostgreSQL</> has
17 become feature-complete in many areas. This release shows a
18 targeted approach to adding features (e.g., authentication,
19 monitoring, space reuse), and adds capabilities defined in the
20 later SQL standards. The major areas of enhancement are:
25 <!-- This list duplicates items below, but without authors or details-->
35 Common Table Expressions and Recursive Queries
41 Default and variadic parameters for functions
59 Per-database locale settings
71 Improved join performance for <literal>EXISTS</> and <literal>NOT EXISTS</> queries
77 Easier-to-use Warm Standby
83 Automatic sizing of the Free Space Map
89 Visibility Map (greatly reduces vacuum overhead for slowly-changing tables)
95 Version-aware psql (backslash commands work against older servers)
101 Support SSL certificates for user authentication
107 Per-function runtime statistics
113 Easy editing of functions in psql
119 New contrib modules: pg_stat_statements, auto_explain, citext, btree_gin
126 The above items are explained in more detail in the sections below.
132 <title>Migration to Version 8.4</title>
135 A dump/restore using <application>pg_dump</application> is
136 required for those wishing to migrate data from any previous
141 Observe the following incompatibilities:
145 <title>General</title>
150 Use 64-bit integer datetimes by default (Neil Conway)
154 Previously this was selected by <application>configure</>'s
155 <option>--enable-integer-datetimes</> option. To retain
156 the old behavior, build with <option>--disable-integer-datetimes</>.
162 Remove <application>ipcclean</> utility command (Bruce)
166 The utility only worked on a few platforms. Users should use
167 their operating system tools instead.
176 <title>Server Settings</title>
181 Change default setting for
182 <literal>log_min_messages</> to <literal>warning</> (previously
183 it was <literal>notice</>) to reduce log file volume (Tom)
189 Change default setting for <literal>max_prepared_transactions</> to
190 zero (previously it was 5) (Tom)
196 Make <literal>debug_print_parse</>, <literal>debug_print_rewritten</>,
197 and <literal>debug_print_plan</>
198 output appear at <literal>LOG</> message level, not
199 <literal>DEBUG1</> as formerly (Tom)
205 Make <literal>debug_pretty_print</> default to <literal>on</> (Tom)
211 Remove <varname>explain_pretty_print</> parameter (no longer needed) (Tom)
217 Make <varname>log_temp_files</> settable by superusers only, like other
218 logging options (Simon Riggs)
224 Remove automatic appending of the epoch timestamp when no <literal>%</>
225 escapes are present in <literal>log_filename</> (Robert Haas)
229 This change was made because some users wanted a fixed log filename,
230 for use with an external log rotation tool.
236 Remove <varname>log_restartpoints</> from <filename>recovery.conf</>;
237 instead use <varname>log_checkpoints</> (Simon)
243 Remove <varname>krb_realm</> and <varname>krb_server_hostname</>;
244 these are now set in <filename>pg_hba.conf</> instead (Magnus)
250 There are also significant changes in <link
251 linkend="release-8-4-pg-hba-conf"><filename>pg_hba.conf</></link>,
261 <title>Queries</title>
267 Change <command>TRUNCATE</> and <command>LOCK</> to
268 apply to child tables of the specified table(s) (Peter)
272 These commands now accept an <literal>ONLY</> option that prevents
273 processing child tables; this option must be used if the old
280 <command>SELECT DISTINCT</> and
281 <literal>UNION</>/<literal>INTERSECT</>/<literal>EXCEPT</>
282 no longer always produce sorted output (Tom)
286 Previously, these types of queries always removed duplicate rows
287 by means of Sort/Unique processing (i.e., sort then remove adjacent
288 duplicates). Now they can be implemented by hashing, which will not
289 produce sorted output. If an application relied on the output being
290 in sorted order, the recommended fix is to add an <literal>ORDER BY</>
291 clause. As a short-term workaround, the previous behavior can be
292 restored by disabling <literal>enable_hashagg</>, but that is a very
293 performance-expensive fix. <literal>SELECT DISTINCT ON</> never uses
294 hashing, however, so its behavior is unchanged.
300 Force child tables to inherit <literal>CHECK</> constraints from parents
301 (Alex Hunsaker, Nikhil Sontakke, Tom)
305 Formerly it was possible to drop such a constraint from a child
306 table, allowing rows that violate the constraint to be visible
307 when scanning the parent table. This was deemed inconsistent,
308 as well as contrary to SQL standard.
314 Disallow negative <literal>LIMIT</> or <literal>OFFSET</>
315 values, rather than treating them as zero (Simon)
321 Disallow <command>LOCK TABLE</> outside a transaction block
326 Such an operation is useless because the lock would be released
333 Sequences now contain an additional <structfield>start_value</> column
338 This supports <command>ALTER SEQUENCE ... RESTART</>.
348 <title>Functions and Operators</title>
354 Make <type>numeric</> zero raised to a fractional power return
355 <literal>0</>, rather than throwing an error, and make
356 <type>numeric</> zero raised to the zero power return <literal>1</>,
357 rather than error (Bruce)
361 This matches the longstanding <type>float8</> behavior.
367 Allow unary minus of floating-point values to produce minus zero (Tom)
371 The changed behavior is more <acronym>IEEE</>-standard
378 Throw an error if an escape character is the last character in
379 a <literal>LIKE</> pattern (i.e., it has nothing to escape) (Tom)
383 Previously, such an escape character was silently ignored,
384 thus possibly masking application logic errors.
390 Remove <literal>~=~</> and <literal>~<>~</> operators
391 formerly used for <literal>LIKE</> index comparisons (Tom)
395 Pattern indexes now use the regular equality operator.
401 <function>xpath()</> now passes its arguments to <application>libxml</>
402 without any changes (Andrew)
406 This means that the XML argument must be a well-formed XML document.
407 The previous coding attempted to allow XML fragments, but it did not
414 Make <function>xmlelement()</> format attribute values just like
415 content values (Peter)
419 Previously, attribute values were formatted according to the
420 normal SQL output behavior, which is sometimes at odds with
427 Rewrite memory management for <application>libxml</>-using functions
432 This change should avoid some compatibility problems with use of
433 <application>libxml</> in PL/Perl and other add-on code.
439 Adopt a faster algorithm for hash functions (Kenneth Marshall,
440 based on work of Bob Jenkins)
444 Many of the built-in hash functions now deliver different results on
445 little-endian and big-endian platforms.
452 <title>Temporal Functions and Operators</title>
458 <varname>DateStyle</> no longer controls <type>interval</> output
459 formatting; instead there is a new variable <varname>IntervalStyle</>
466 Improve consistency of handling of fractional seconds in
467 <type>timestamp</> and <type>interval</> output (Ron Mayer)
471 This may result in displaying a different number of fractional
472 digits than before, or rounding instead of truncating.
478 Make <function>to_char()</>'s localized month/day names depend
479 on <varname>LC_TIME</>, not <varname>LC_MESSAGES</> (Euler
486 Cause <function>to_date()</> and <function>to_timestamp()</>
487 to more consistently report errors for invalid input (Brendan
492 Previous versions would often ignore or silently misread input
493 that did not match the format string. Such cases will now
500 Fix <function>to_timestamp()</> to not require upper/lower case
501 matching for meridian (<literal>AM</>/<literal>PM</>) and era
502 (<literal>BC</>/<literal>AD</>) format designations (Brendan
507 For example, input value <literal>ad</> now matches the format
508 string <literal>AD</>.
521 <title>Changes</title>
524 Below you will find a detailed account of the changes between
525 <productname>PostgreSQL</productname> 8.4 and the previous major
530 <title>Performance</title>
535 Improve optimizer statistics calculations (Jan Urbanski, Tom)
539 In particular, estimates for full-text-search operators are
546 Allow <command>SELECT DISTINCT</> and
547 <literal>UNION</>/<literal>INTERSECT</>/<literal>EXCEPT</> to
552 This means that these types of queries no longer automatically
553 produce sorted output.
559 Create explicit concepts of semi-joins and anti-joins (Tom)
563 This work formalizes our previous ad-hoc treatment of <literal>IN
564 (SELECT ...)</> clauses, and extends it to <literal>EXISTS</> and
565 <literal>NOT EXISTS</> clauses. It should result in significantly
566 better planning of <literal>EXISTS</> and <literal>NOT EXISTS</>
567 queries. In general, logically equivalent <literal>IN</> and
568 <literal>EXISTS</> clauses should now have similar performance,
569 whereas previously <literal>IN</> often won.
575 Improve optimization of sub-selects beneath outer joins (Tom)
579 Formerly, a sub-select or view could not be optimized very well if it
580 appeared within the nullable side of an outer join and contained
581 non-strict expressions (for instance, constants) in its result list.
587 Improve the performance of <function>text_position()</> and
588 related functions by using Boyer-Moore-Horspool searching (David
593 This is particularly helpful for long search patterns.
599 Reduce I/O load of writing the statistics collection file
600 by writing the file only when requested (Martin Pihlak)
606 Improve performance for bulk inserts (Robert Haas, Simon)
612 Increase the default value of <varname>default_statistics_target</>
613 from <literal>10</> to <literal>100</> (Greg Sabino Mullane,
618 The maximum value was also increased from <literal>1000</> to
625 Perform <varname>constraint_exclusion</> checking by default
626 in queries involving inheritance or <literal>UNION ALL</> (Tom)
630 A new <varname>constraint_exclusion</> setting,
631 <literal>partition</>, was added to specify this behavior.
637 Allow I/O read-ahead for bitmap index scans (Greg Stark)
641 The amount of read-ahead is controlled by
642 <varname>effective_io_concurrency</>. This feature is available only
643 if the kernel has <function>posix_fadvise()</> support.
649 Inline simple set-returning <acronym>SQL</> functions in
650 <literal>FROM</> clauses (Richard Rowell)
656 Improve performance of multi-batch hash joins by providing a special
657 case for join key values that are especially common in the outer
658 relation (Bryce Cutt, Ramon Lawrence)
664 Reduce volume of temporary data in multi-batch hash joins
665 by suppressing <quote>physical tlist</> optimization (Michael
666 Henderson, Ramon Lawrence)
672 Avoid waiting for idle-in-transaction sessions during
673 <command>CREATE INDEX CONCURRENTLY</> (Simon)
679 Improve performance of shared cache invalidation (Tom)
688 <title>Server</title>
691 <title>Settings</title>
697 Convert many <filename>postgresql.conf</> settings to enumerated
698 values so that <literal>pg_settings</> can display the valid
705 Add <varname>cursor_tuple_fraction</> parameter to control the
706 fraction of a cursor's rows that the planner assumes will be
707 fetched (Robert Hell)
713 Allow underscores in the names of custom variable
714 classes in <filename>postgresql.conf</> (Tom)
723 <title>Authentication and security</title>
728 Remove support for the (insecure) <literal>crypt</> authentication method
733 This effectively obsoletes pre-<productname>PostgreSQL</> 7.2 client
734 libraries, as there is no longer any non-plaintext password method that
741 Support regular expressions in <filename>pg_ident.conf</>
748 Allow <productname>Kerberos</>/<acronym>GSSAPI</> parameters
749 to be changed without restarting the postmaster (Magnus)
755 Support <acronym>SSL</> certificate chains in server certificate
760 Including the full certificate chain makes the client able
761 to verify the certificate without having all intermediate CA
762 certificates present in the local store, which is often the case for
769 Report appropriate error message for combination of <literal>MD5</>
770 authentication and <varname>db_user_namespace</> enabled (Bruce)
777 <sect4 id="release-8-4-pg-hba-conf">
778 <title><filename>pg_hba.conf</></title>
783 Change all authentication options to use <literal>name=value</>
788 This makes incompatible changes to the <literal>ldap</>,
789 <literal>pam</> and <literal>ident</> authentication methods. All
790 <filename>pg_hba.conf</> entries with these methods need to be
791 rewritten using the new format.
797 Remove the <literal>ident sameuser</> option, instead making that
798 behavior the default if no usermap is specified (Magnus)
804 Allow a usermap parameter for all external authentication methods
809 Previously a usermap was only supported for <literal>ident</>
816 Add <literal>clientcert</> option to control requesting of a
817 client certificate (Magnus)
821 Previously this was controlled by the presence of a root
822 certificate file in the server's data directory.
828 Add <literal>cert</> authentication method to allow
829 <emphasis>user</> authentication via <acronym>SSL</> certificates
834 Previously <acronym>SSL</> certificates could only verify that
835 the client had access to a certificate, not authenticate a
842 Allow <literal>krb5</>, <literal>gssapi</> and <literal>sspi</>
843 realm and <literal>krb5</> host settings to be specified in
844 <filename>pg_hba.conf</> (Magnus)
848 These override the settings in <filename>postgresql.conf</>.
854 Add <varname>include_realm</> parameter for <literal>krb5</>,
855 <literal>gssapi</>, and <literal>sspi</> methods (Magnus)
859 This allows identical usernames from different realms to be
860 authenticated as different database users using usermaps.
866 Parse <filename>pg_hba.conf</> fully when it is loaded,
867 so that errors are reported immediately (Magnus)
871 Previously, most errors in the file wouldn't be detected until clients
872 tried to connect, so an erroneous file could render the system
873 unusable. With the new behavior, if an error is detected during
874 reload then the bad file is rejected and the postmaster continues
881 Show all parsing errors in <filename>pg_hba.conf</> instead of
882 aborting after the first one (Selena Deckelmann)
888 Support <literal>ident</> authentication over Unix-domain sockets
889 on <productname>Solaris</> (Garick Hamlin)
898 <title>Continuous Archiving</title>
903 Provide an option to <function>pg_start_backup()</> to force its
904 implied checkpoint to finish as quickly as possible (Tom)
908 The default behavior avoids excess I/O consumption, but that is
909 pointless if no concurrent query activity is going on.
915 Make <function>pg_stop_backup()</> wait for modified <acronym>WAL</>
916 files to be archived (Simon)
920 This guarantees that the backup is valid at the time
921 <function>pg_stop_backup()</> completes.
927 When archiving is enabled, rotate the last WAL segment at shutdown
928 so that all transactions can be archived immediately
929 (Guillaume Smet, Heikki)
935 Delay <quote>smart</> shutdown while a continuous archiving base backup
936 is in progress (Laurenz Albe)
942 Cancel a continuous archiving base backup if <quote>fast</> shutdown
943 is requested (Laurenz Albe)
949 Allow <filename>recovery.conf</> boolean variables to take the
950 same range of string values as <filename>postgresql.conf</>
961 <title>Monitoring</title>
966 Add <function>pg_conf_load_time()</> to report when
967 the <productname>PostgreSQL</> configuration files were last loaded
974 Add <function>pg_terminate_backend()</> to safely terminate a
975 backend (the <literal>SIGTERM</> signal works also) (Tom, Bruce)
979 While it's always been possible to <literal>SIGTERM</> a single
980 backend, this was previously considered unsupported; and testing
981 of the case found some bugs that are now fixed.
987 Add ability to track user-defined functions' call counts and
988 runtimes (Martin Pihlak)
992 Function statistics appear in a new system view,
993 <literal>pg_stat_user_functions</>. Tracking is controlled
994 by the new parameter <varname>track_functions</>.
1000 Allow specification of the maximum query string size in
1001 <literal>pg_stat_activity</> via new
1002 <varname>track_activity_query_size</> parameter (Thomas Lee)
1008 Increase the maximum line length sent to <application>syslog</>, in
1009 hopes of improving performance (Tom)
1015 Add read-only configuration variables <varname>segment_size</>,
1016 <varname>wal_block_size</>, and <varname>wal_segment_size</>
1023 When reporting a deadlock, report the text of all queries involved
1024 in the deadlock to the server log (Itagaki Takahiro)
1030 Add <function>pg_stat_get_activity(pid)</> function to return
1031 information about a specific process id (Magnus)
1037 Allow the location of the server's statistics file to be specified
1038 via <varname>stats_temp_directory</> (Magnus)
1042 This allows the statistics file to be placed in a
1043 <acronym>RAM</>-resident directory to reduce I/O requirements.
1044 On startup/shutdown, the file is copied to its traditional location
1045 (<literal>$PGDATA/global/</>) so it is preserved across restarts.
1056 <title>Queries</title>
1061 Add support for <literal>WINDOW</> functions (Hitoshi Harada)
1067 Add support for <literal>WITH</> clauses (CTEs), including <literal>WITH
1068 RECURSIVE</> (Yoshiyuki Asaba, Tatsuo Ishii, Tom)
1074 Add <command>TABLE</> command (Peter)
1078 <literal>TABLE tablename</> is a SQL standard short-hand for
1079 <literal>SELECT * FROM tablename</>.
1085 Allow <literal>AS</> to be optional when specifying a
1086 <command>SELECT</> (or <literal>RETURNING</>) column output
1087 label (Hiroshi Saito)
1091 This works so long as the column label is not any
1092 <productname>PostgreSQL</> keyword; otherwise <literal>AS</> is still
1099 Support set-returning functions in <command>SELECT</> result lists
1100 even for functions that return their result via a tuplestore (Tom)
1104 In particular, this means that functions written in PL/PgSQL
1105 and other PL languages can now be called this way.
1111 Support set-returning functions in the output of aggregation
1112 and grouping queries (Tom)
1118 Allow <command>SELECT FOR UPDATE</>/<literal>SHARE</> to work
1119 on inheritance trees (Tom)
1125 Add infrastructure for <acronym>SQL/MED</> (Martin Pihlak,
1130 There are no remote or external <acronym>SQL/MED</> capabilities
1131 yet, but this change provides a standardized and future-proof
1132 system for managing connection information for modules like
1133 <filename>dblink</> and <filename>plproxy</>.
1139 Invalidate cached plans when referenced schemas, functions, operators,
1140 or operator classes are modified (Martin Pihlak, Tom)
1144 This improves the system's ability to respond to on-the-fly
1150 Allow comparison of composite types and allow arrays of
1151 anonymous composite types (Tom)
1155 This allows constructs such as
1156 <literal>row(1, 1.1) = any (array[row(7, 7.7), row(1, 1.0)])</>.
1157 This is particularly useful in recursive queries.
1163 Add support for Unicode string literal and identifier specifications
1164 using code points, e.g. <literal>U&'d\0061t\+000061'</>
1171 Reject <literal>\000</> in string literals and <command>COPY</> data
1176 Previously, this was accepted but had the effect of terminating
1177 the string contents.
1183 Improve the parser's ability to report error locations (Tom)
1187 An error location is now reported for many semantic errors,
1188 such as mismatched datatypes, that previously could not be localized.
1195 <title><command>TRUNCATE</></title>
1200 Support statement-level <literal>ON TRUNCATE</> triggers (Simon)
1206 Add <literal>RESTART</>/<literal>CONTINUE IDENTITY</> options
1207 for <command>TRUNCATE TABLE</>
1208 (Zoltan Boszormenyi)
1212 The start value of a sequence can be changed by <command>ALTER
1213 SEQUENCE START WITH</>.
1219 Allow <command>TRUNCATE tab1, tab1</> to succeed (Bruce)
1225 Add a separate <command>TRUNCATE</> permission (Robert Haas)
1234 <title><command>EXPLAIN</></title>
1239 Make <command>EXPLAIN VERBOSE</> show the output columns of each
1244 Previously <command>EXPLAIN VERBOSE</> output an internal
1245 representation of the query plan. (That behavior is now
1246 available via <varname>debug_print_plan</>.)
1252 Make <command>EXPLAIN</> identify subplans and initplans with
1253 individual labels (Tom)
1259 Make <command>EXPLAIN</> honor <varname>debug_print_plan</> (Tom)
1265 Allow <command>EXPLAIN</> on <command>CREATE TABLE AS</> (Peter)
1274 <title><literal>LIMIT</>/<literal>OFFSET</></title>
1279 Allow sub-selects in <literal>LIMIT</> and <literal>OFFSET</> (Tom)
1285 Add <acronym>SQL</>-standard syntax for
1286 <literal>LIMIT</>/<literal>OFFSET</> capabilities (Peter)
1291 <literal>OFFSET num {ROW|ROWS} FETCH {FIRST|NEXT} [num] {ROW|ROWS}
1303 <title>Object Manipulation</title>
1308 Add support for column-level privileges (Stephen Frost, KaiGai
1315 Refactor multi-object <command>DROP</> operations to reduce the
1316 need for <literal>CASCADE</> (Alex Hunsaker)
1320 For example, if table <literal>B</> has a dependency on table
1321 <literal>A</>, the command <literal>DROP TABLE A, B</> no longer
1322 requires the <literal>CASCADE</> option.
1328 Fix various problems with concurrent <command>DROP</> commands
1329 by ensuring that locks are taken before we begin to drop dependencies
1336 Improve reporting of dependencies during <command>DROP</>
1343 Add <literal>WITH [NO] DATA</> clause to <command>CREATE TABLE
1344 AS</>, per the <acronym>SQL</> standard (Peter, Tom)
1350 Add support for user-defined I/O conversion casts (Heikki)
1356 Allow <command>CREATE AGGREGATE</> to use an <type>internal</>
1357 transition datatype (Tom)
1363 Add <literal>LIKE</> clause to <command>CREATE TYPE</> (Tom)
1367 This simplifies creation of data types that use the same internal
1368 representation as an existing type.
1374 Allow specification of the type category and <quote>preferred</>
1375 status for user-defined base types (Tom)
1379 This allows more control over the coercion behavior of user-defined
1386 Allow <command>CREATE OR REPLACE VIEW</> to add columns to the
1387 end of a view (Robert Haas)
1394 <title><command>ALTER</></title>
1399 Add <command>ALTER TYPE RENAME</> (Petr Jelinek)
1405 Add <command>ALTER SEQUENCE ... RESTART</> (with no parameter) to
1406 reset a sequence to its initial value (Zoltan Boszormenyi)
1412 Modify the <command>ALTER TABLE</> syntax to allow all reasonable
1413 combinations for tables, indexes, sequences, and views (Tom)
1417 This change allows the following new syntaxes:
1422 <command>ALTER SEQUENCE OWNER TO</>
1427 <command>ALTER VIEW ALTER COLUMN SET/DROP DEFAULT</>
1432 <command>ALTER VIEW OWNER TO</>
1437 <command>ALTER VIEW SET SCHEMA</>
1442 There is no actual new functionality here, but formerly
1443 you had to say <command>ALTER TABLE</> to do these things,
1444 which was confusing.
1450 Add support for the syntax <command>ALTER TABLE ... ALTER COLUMN
1451 ... SET DATA TYPE</> (Peter)
1455 This is <acronym>SQL</>-standard syntax for functionality that
1456 was already supported.
1462 Make <command>ALTER TABLE SET WITHOUT OIDS</> rewrite the table
1463 to physically remove <type>OID</> values (Tom)
1467 Also, add <command>ALTER TABLE SET WITH OIDS</> to rewrite the
1468 table to add <type>OID</>s.
1477 <title>Database Manipulation</title>
1482 Improve reporting of
1483 <command>CREATE</>/<command>DROP</>/<command>RENAME DATABASE</>
1484 failure when uncommitted prepared transactions are the cause
1491 Make <varname>LC_COLLATE</> and <varname>LC_CTYPE</> into
1492 per-database settings (Radek Strnad, Heikki)
1496 This makes collation similar to encoding, which was always
1497 configurable per database.
1503 Improve checks that the database encoding, collation
1504 (<varname>LC_COLLATE</>), and character classes
1505 (<varname>LC_CTYPE</>) match (Heikki, Tom)
1509 Note in particular that a new database's encoding and locale
1510 settings can be changed only when copying from <literal>template0</>.
1511 This prevents possibly copying data that doesn't match the settings.
1517 Add <command>ALTER DATABASE SET TABLESPACE</> to move a database
1518 to a new tablespace (Guillaume Lelarge, Bernd Helmle)
1529 <title>Utility Operations</title>
1535 Add a <literal>VERBOSE</> option to the <command>CLUSTER</> command and
1536 <application>clusterdb</> (Jim Cox)
1542 Decrease memory requirements for recording pending trigger
1550 <title>Indexes</title>
1555 Dramatically improve the speed of building and accessing hash
1556 indexes (Tom Raney, Shreya Bhargava)
1560 This allows hash indexes to be sometimes faster than btree
1561 indexes. However, hash indexes are still not crash-safe.
1567 Make hash indexes store only the hash code, not the full value of
1568 the indexed column (Xiao Meng)
1572 This greatly reduces the size of hash indexes for long indexed
1573 values, improving performance.
1579 Implement fast update option for GIN indexes (Teodor, Oleg)
1583 This option greatly improves update speed at a small penalty in search
1590 <literal>xxx_pattern_ops</> indexes can now be used for simple
1591 equality comparisons, not only for <literal>LIKE</> (Tom)
1600 <title>Full Text Indexes</title>
1605 Remove the requirement to use <literal>@@@</> when doing
1606 <acronym>GIN</> weighted lookups on full text indexes (Tom, Teodor)
1610 The normal <literal>@@</> text search operator can be used
1617 Add an optimizer selectivity function for <literal>@@</> text
1618 search operations (Jan Urbanski)
1624 Allow prefix matching in full text searches (Teodor Sigaev,
1631 Support multi-column <acronym>GIN</> indexes (Teodor Sigaev)
1637 Improve support for Nepali language and Devanagari alphabet (Teodor)
1646 <title><command>VACUUM</></title>
1651 Track free space in separate per-relation <quote>fork</> files (Heikki)
1655 Free space discovered by <command>VACUUM</> is now recorded in
1656 <filename>*_fsm</> files, rather than in a fixed-sized shared memory
1657 area. The <varname>max_fsm_pages</> and <varname>max_fsm_relations</>
1658 settings have been removed, greatly simplifying administration of
1659 free space management.
1665 Add a visibility map to track pages that do not require
1670 This allows <command>VACUUM</> to avoid scanning all of
1671 a table when only a portion of the table needs vacuuming.
1672 The visibility map is stored in per-relation <quote>fork</> files.
1678 Add <varname>vacuum_freeze_table_age</> parameter to control
1679 when <command>VACUUM</> should ignore the visibility map and
1680 do a full table scan to freeze tuples (Heikki)
1686 Track transaction snapshots more carefully (Alvaro)
1690 This improves <command>VACUUM</>'s ability to reclaim space
1691 in the presence of long-running transactions.
1697 Add ability to specify per-relation autovacuum and <acronym>TOAST</>
1698 parameters in <command>CREATE TABLE</> (Alvaro, Euler Taveira de
1703 Autovacuum options used to be stored in a system table.
1709 Add <literal>--freeze</> option to <application>vacuumdb</>
1721 <title>Data Types</title>
1726 Add a <literal>CaseSensitive</> option for text search synonym
1727 dictionaries (Simon)
1733 Improve the precision of <type>NUMERIC</> division (Tom)
1739 Add basic arithmetic operators for <type>int2</> with <type>int8</>
1744 This eliminates the need for explicit casting in some situations.
1750 Allow <type>UUID</> input to accept an optional hyphen after
1751 every fourth digit (Robert Haas)
1757 Allow <literal>on</>/<literal>off</> as input for the boolean data type
1764 Allow spaces around <literal>NaN</> in the input string for
1765 type <type>numeric</> (Sam Mason)
1772 <title>Temporal Data Types</title>
1777 Reject year <literal>0 BC</> and years <literal>000</> and
1778 <literal>0000</> (Tom)
1782 Previously these were interpreted as <literal>1 BC</>.
1783 (Note: years <literal>0</> and <literal>00</> are still assumed to be
1790 Include <literal>SGT</> (Singapore time) in the default list of
1791 known time zone abbreviations (Tom)
1797 Support <literal>infinity</> and <literal>-infinity</> as
1798 values of type <type>date</> (Tom)
1804 Make parsing of <type>interval</> literals more standard-compliant
1809 For example, <literal>INTERVAL '1' YEAR</> now does what it's
1816 Allow <type>interval</> fractional-seconds precision to be specified
1817 after the <literal>second</> keyword, for <acronym>SQL</> standard
1822 Formerly the precision had to be specified after the keyword
1823 <type>interval</>. (For backwards compatibility, this syntax is still
1824 supported, though deprecated.) Data type definitions will now be
1825 output using the standard format.
1831 Support the <acronym>IS0 8601</> <type>interval</> syntax (Ron
1832 Mayer, Kevin Grittner)
1836 For example, <literal>INTERVAL 'P1Y2M3DT4H5M6.7S'</> is now
1843 Add <varname>IntervalStyle</> parameter
1844 which controls how <type>interval</> values are output (Ron Mayer)
1848 Valid values are: <literal>postgres</>, <literal>postgres_verbose</>,
1849 <literal>sql_standard</>, <literal>iso_8601</>. This setting also
1850 controls the handling of negative <type>interval</> input when only
1851 some fields have positive/negative designations.
1857 Improve consistency of handling of fractional seconds in
1858 <type>timestamp</> and <type>interval</> output (Ron Mayer)
1867 <title>Arrays</title>
1872 Improve the handling of casts applied to <literal>ARRAY[]</>
1873 constructs, such as <literal>ARRAY[...]::integer[]</>
1878 Formerly <productname>PostgreSQL</> attempted to determine a data type
1879 for the <literal>ARRAY[]</> construct without reference to the ensuing
1880 cast. This could fail unnecessarily in many cases, in particular when
1881 the <literal>ARRAY[]</> construct was empty or contained only
1882 ambiguous entries such as <literal>NULL</>. Now the cast is consulted
1883 to determine the type that the array elements must be.
1889 Make <acronym>SQL</>-syntax <type>ARRAY</> dimensions optional
1890 to match the <acronym>SQL</> standard (Peter)
1896 Add <function>array_ndims()</> to return the number
1897 of dimensions of an array (Robert Haas)
1903 Add <function>array_length()</> to return the length
1904 of an array for a specified dimension (Jim Nasby, Robert
1905 Haas, Peter Eisentraut)
1911 Add aggregate function <function>array_agg()</>, which
1912 returns all aggregated values as a single array (Robert Haas,
1919 Add <function>unnest()</>, which converts an array to
1920 individual row values (Tom)
1924 This is the opposite of <function>array_agg()</>.
1930 Add <function>array_fill()</> to create arrays initialized with
1931 a value (Pavel Stehule)
1937 Add <function>generate_subscripts()</> to simplify generating
1938 the range of an array's subscripts (Pavel Stehule)
1947 <title>Wide-Value Storage (<acronym>TOAST</>)</title>
1952 Consider <acronym>TOAST</> compression on values as short as
1953 32 bytes (previously 256 bytes) (Greg Stark)
1959 Require 25% minimum space savings before using <acronym>TOAST</>
1960 compression (previously 20% for small values and any-savings-at-all
1961 for large values) (Greg)
1967 Improve <acronym>TOAST</> heuristics for rows that have a mix of large
1968 and small toastable fields, so that we prefer to push large values out
1969 of line and don't compress small values unnecessarily (Greg, Tom)
1980 <title>Functions</title>
1985 Document that <function>setseed()</> allows values from
1986 <literal>-1</> to <literal>1</> (not just <literal>0</> to
1987 <literal>1</>), and enforce the valid range (Kris Jurka)
1993 Add server-side function <function>lo_import(filename, oid)</>
2000 Add <function>quote_nullable()</>, which behaves like
2001 <function>quote_literal()</> but returns the string <literal>NULL</> for
2002 a null argument (Brendan Jurd)
2008 Improve full text search <function>headline()</> function to
2009 allow extracting several fragments of text (Sushant Sinha)
2015 Add <function>suppress_redundant_updates_trigger()</> trigger
2016 function to avoid overhead for non-data-changing updates (Andrew)
2022 Add <function>div(numeric, numeric)</> to perform <type>numeric</>
2023 division without rounding (Tom)
2029 Add <type>timestamp</> and <type>timestamptz</> versions of
2030 <function>generate_series()</> (Hitoshi Harada)
2037 <title>Object Information Functions</title>
2042 Implement <function>current_query()</> for use by functions
2043 that need to know the currently running query (Tomas Doran)
2049 Add <function>pg_get_keywords()</> to return a list of the
2050 parser keywords (Dave Page)
2056 Add <function>pg_get_functiondef()</> to see a function's
2057 definition (Abhijit Menon-Sen)
2063 Allow the second argument of <function>pg_get_expr()</> to be zero
2064 when deparsing an expression that does not contain variables (Tom)
2070 Modify <function>pg_relation_size()</> to use <literal>regclass</>
2075 <function>pg_relation_size(data_type_name)</> no longer works.
2081 Add <literal>boot_val</> and <literal>reset_val</> columns to
2082 <literal>pg_settings</> output (Greg Smith)
2088 Add source file name and line number columns to
2089 <literal>pg_settings</> output for variables set in a configuration
2090 file (Magnus, Alvaro)
2094 For security reasons, these columns are only visible to superusers.
2100 Add support for <varname>CURRENT_CATALOG</>,
2101 <varname>CURRENT_SCHEMA</>, <varname>SET CATALOG</>, <varname>SET
2106 These provide <acronym>SQL</>-standard syntax for existing features.
2112 Add <function>pg_typeof()</> which returns the data type
2113 of any value (Brendan Jurd)
2119 Make <function>version()</> return information about whether
2120 the server is a 32- or 64-bit binary (Bruce)
2126 Fix the behavior of information schema columns
2127 <structfield>is_insertable_into</> and <structfield>is_updatable</> to
2128 be consistent (Peter)
2134 Improve the behavior of information schema
2135 <structfield>datetime_precision</> columns (Peter)
2139 These columns now show zero for <type>date</> columns, and 6
2140 (the default precision) for <type>time</>, <type>timestamp</>, and
2141 <type>interval</> without a declared precision, rather than showing
2148 Convert remaining builtin set-returning functions to use
2149 <literal>OUT</> parameters (Jaime Casanova)
2153 This makes it possible to call these functions without specifying
2154 a column list: <function>pg_show_all_settings()</>,
2155 <function>pg_lock_status()</>, <function>pg_prepared_xact()</>,
2156 <function>pg_prepared_statement()</>, <function>pg_cursor()</>
2162 Make <function>pg_*_is_visible()</> and
2163 <function>has_*_privilege()</> functions return <literal>NULL</>
2164 for invalid OIDs, rather than reporting an error (Tom)
2170 Extend <function>has_*_privilege()</> functions to allow inquiring
2171 about the OR of multiple privileges in one call (Stephen
2178 Add <function>has_column_privilege()</> and
2179 <function>has_any_column_privilege()</> functions (Stephen
2189 <title>Function Creation</title>
2194 Support variadic functions (functions with a variable number
2195 of arguments) (Pavel Stehule)
2199 Only trailing arguments can be optional, and they all must be
2200 of the same data type.
2206 Support default values for function arguments (Pavel Stehule)
2212 Add <command>CREATE FUNCTION ... RETURNS TABLE</> clause (Pavel
2219 Allow <acronym>SQL</>-language functions to return the output
2220 of an <command>INSERT</>/<command>UPDATE</>/<command>DELETE</>
2221 <literal>RETURNING</> clause (Tom)
2230 <title>PL/PgSQL Server-Side Language</title>
2235 Support <literal>EXECUTE USING</> for easier insertion of data
2236 values into a dynamic query string (Pavel Stehule)
2242 Allow looping over the results of a cursor using a <literal>FOR</>
2243 loop (Pavel Stehule)
2249 Support <literal>RETURN QUERY EXECUTE</> (Pavel
2256 Improve the <literal>RAISE</> command (Pavel Stehule)
2261 Support <literal>DETAIL</> and <literal>HINT</> fields
2266 Support specification of the <literal>SQLSTATE</> error code
2271 Support an exception name parameter
2276 Allow <literal>RAISE</> without parameters in an exception
2277 block to re-throw the current error
2286 Allow specification of <varname>SQLSTATE</> codes
2287 in <literal>EXCEPTION</> lists (Pavel Stehule)
2291 This is useful for handling custom <varname>SQLSTATE</> codes.
2297 Support the <literal>CASE</> statement (Pavel Stehule)
2303 Make <command>RETURN QUERY</> set the special <literal>FOUND</> and
2304 <command>GET DIAGNOSTICS</> <literal>ROW_COUNT</> variables
2311 Make <command>FETCH</> and <command>MOVE</> set the
2312 <command>GET DIAGNOSTICS</> <literal>ROW_COUNT</> variable
2319 Make <command>EXIT</> without a label always exit the innermost
2324 Formerly, if there were a <literal>BEGIN</> block more closely nested
2325 than any loop, it would exit that block instead. The new behavior
2326 matches Oracle(TM) and is also what was previously stated by our own
2333 Make processing of string literals and nested block comments
2334 match the main SQL parser's processing (Tom)
2338 In particular, the format string in <command>RAISE</> now works
2339 the same as any other string literal, including being subject
2340 to <varname>standard_conforming_strings</>. This change also
2341 fixes other cases in which valid commands would fail when
2342 <varname>standard_conforming_strings</> is on.
2348 Avoid memory leakage when the same function is called at varying
2349 exception-block nesting depths (Tom)
2360 <title>Client Applications</title>
2366 Fix <literal>pg_ctl restart</> to preserve command-line arguments
2373 Add <literal>-w</>/<literal>--no-password</> option that
2374 prevents password prompting in all utilities that have a
2375 <literal>-W</>/<literal>--password</> option (Peter)
2381 Remove <option>-q</> (quiet) option of <application>createdb</>,
2382 <application>createuser</>, <application>dropdb</>,
2383 <application>dropuser</> (Peter)
2387 These options have had no effect since <productname>PostgreSQL</>
2395 <title><application>psql</></title>
2400 Remove verbose startup banner; now just suggest <literal>help</>
2407 Make <literal>help</> show common backslash commands (Greg
2414 Add <literal>\pset format wrapped</> mode to wrap output to the
2415 screen width, or file/pipe output too if <literal>\pset columns</>
2416 is set (Bryce Nesbitt)
2422 Allow all supported spellings of boolean values in <command>\pset</>,
2423 rather than just <literal>on</> and <literal>off</> (Bruce)
2427 Formerly, any string other than <quote>off</> was silently taken
2428 to mean <literal>true</>. <application>psql</> will now complain
2429 about unrecognized spellings (but still take them as <literal>true</>).
2435 Use the pager for wide output (Bruce)
2441 Require a space between a one-letter backslash command and its first
2442 argument (Bernd Helmle)
2446 This removes a historical source of ambiguity.
2452 Improve tab completion support for schema-qualified and
2453 quoted identifiers (Greg Sabino Mullane)
2459 Add optional <literal>on</>/<literal>off</> argument for
2460 <command>\timing</> (David Fetter)
2466 Display access control rights on multiple lines (Brendan
2467 Jurd, Andreas Scherbaum)
2473 Make <command>\l</> show database access privileges (Andrew Gilligan)
2479 Make <command>\l+</> show database sizes, if permissions
2480 allow (Andrew Gilligan)
2486 Add the <command>\ef</> command to edit function definitions
2496 <title><application>psql</> \d* commands</title>
2502 Make <command>\d*</> commands that do not have a pattern argument
2503 show system objects only if the <literal>S</> modifier is specified
2504 (Greg Sabino Mullane, Bruce)
2508 The former behavior was inconsistent across different variants
2509 of <command>\d</>, and in most cases it provided no easy way to see
2516 Improve <command>\d*</> commands to work with older
2517 <productname>PostgreSQL</> server versions (back to 7.4),
2518 not only the current server version
2525 Make <command>\d</> show foreign-key constraints that reference
2526 the selected table (Kenneth D'Souza)
2532 Make <command>\d</> on a sequence show its column values
2533 (Euler Taveira de Oliveira)
2539 Add column storage type and other relation options to the
2540 <command>\d+</> display (Gregory Stark, Euler Taveira de
2547 Show relation size in <command>\dt+</> output (Dickson S.
2554 Show the possible values of <literal>enum</> types in <command>\dT+</>
2561 Allow <command>\dC</> to accept a wildcard pattern, which matches
2562 either datatype involved in the cast (Tom)
2568 Add a function type column to <command>\df</>'s output, and add
2569 options to list only selected types of functions (David Fetter)
2575 Make <command>\df</> not hide functions that take or return
2576 type <type>cstring</> (Tom)
2580 Previously, such functions were hidden because most of them are
2581 datatype I/O functions, which were deemed uninteresting. The new
2582 policy about hiding system functions by default makes this wart
2592 <title><application>pg_dump</></title>
2597 Add a <literal>--no-tablespaces</> option to
2598 <application>pg_dump</>/<application>pg_dumpall</>/<application>pg_restore</>
2599 so that dumps can be restored to clusters that have non-matching
2600 tablespace layouts (Gavin Roy)
2606 Remove <option>-d</> and <option>-D</> options from
2607 <application>pg_dump</> and <application>pg_dumpall</> (Tom)
2611 These options were too frequently confused with the option to
2612 select a database name in other <productname>PostgreSQL</>
2613 client applications. The functionality is still available,
2614 but you must now spell out the long option name
2615 <option>--inserts</> or <option>--column-inserts</>.
2621 Remove <option>-i</>/<option>--ignore-version</> option from
2622 <application>pg_dump</> and <application>pg_dumpall</> (Tom)
2626 Use of this option does not throw an error, but it has no
2627 effect. This option was removed because the version checks
2628 are necessary for safety.
2634 Disable <varname>statement_timeout</> during dump and restore
2641 Add <application>pg_dump</>/<application>pg_dumpall</> option
2642 <option>--lock-wait-timeout</> (David Gould)
2646 This allows dumps to fail if unable to acquire a shared lock
2647 within the specified amount of time.
2653 Reorder <application>pg_dump</> <literal>--data-only</> output
2654 to dump tables referenced by foreign keys before
2655 the referencing tables (Tom)
2659 This allows data loads when foreign keys are already present.
2660 If circular references make a safe ordering impossible, a
2661 <literal>NOTICE</> is issued.
2667 Allow <application>pg_dump</>, <application>pg_dumpall</>, and
2668 <application>pg_restore</> to use a specified role (Benedek
2675 Allow <application>pg_restore</> to use multiple concurrent
2676 connections to do the restore (Andrew)
2680 The number of concurrent connections is controlled by the option
2681 <literal>--jobs</>. This is supported only for custom-format archives.
2692 <title>Programming Tools</title>
2695 <title><application>libpq</></title>
2700 Allow the <type>OID</> to be specified when importing a large
2701 object, via new function <function>lo_import_with_oid()</> (Tatsuo)
2707 Add <quote>events</> support (Andrew Chernow, Merlin Moncure)
2711 This adds the ability to register callbacks to manage private
2712 data associated with <structname>PGconn</> and <structname>PGresult</>
2719 Improve error handling to allow the return of multiple
2720 error messages as multi-line error reports (Magnus)
2726 Make <function>PQexecParams()</> and related functions return
2727 <varname>PGRES_EMPTY_QUERY</> for an empty query (Tom)
2731 They previously returned <varname>PGRES_COMMAND_OK</>.
2737 Document how to avoid the overhead of <function>WSACleanup()</>
2738 on Windows (Andrew Chernow)
2744 Do not rely on Kerberos tickets to determine the default database
2749 Previously, a Kerberos-capable build of libpq would use the
2750 principal name from any available Kerberos ticket as default
2751 database username, even if the connection wasn't using Kerberos
2752 authentication. This was deemed inconsistent and confusing.
2753 The default username is now determined the same way with or
2754 without Kerberos. Note however that the database username must still
2755 match the ticket when Kerberos authentication is used.
2763 <title><application>libpq</> <acronym>SSL</> (Secure Sockets Layer)
2769 Fix certificate validation for <acronym>SSL</> connections
2774 <application>libpq</> now supports verifying both the certificate
2775 and the name of the server when making <acronym>SSL</>
2776 connections. If a root certificate is not available to use for
2777 verification, <acronym>SSL</> connections will fail. The
2778 <literal>sslmode</> parameter is used to enable certificate
2779 verification and set the level of checking.
2780 The default is still not to do any verification, allowing connections
2781 to SSL-enabled servers without requiring a root certificate on the
2788 Support wildcard server certificates (Magnus)
2792 If a certificate <acronym>CN</> starts with <literal>*</>, it will
2793 be treated as a wildcard when matching the hostname, allowing the
2794 use of the same certificate for multiple servers.
2800 Allow the file locations for client certificates to be specified
2801 (Mark Woodward, Alvaro, Magnus)
2807 Add a <function>PQinitOpenSSL</> function to allow greater control
2808 over OpenSSL/libcrypto initialization (Andrew Chernow)
2814 Make <application>libpq</> unregister its <application>OpenSSL</>
2815 callbacks when no database connections remain open
2816 (Bruce, Magnus, Russell Smith)
2820 This is required for applications that unload the libpq library,
2821 otherwise invalid <application>OpenSSL</> callbacks will remain.
2830 <title><application>ecpg</></title>
2835 Add localization support for messages (Euler Taveira de
2842 ecpg parser is now automatically generated from the server
2847 Previously the ecpg parser was hand-maintained.
2856 <title>Server Programming Interface (<acronym>SPI</>)</title>
2861 Add support for single-use plans with out-of-line
2868 Add new <varname>SPI_OK_REWRITTEN</> return code for
2869 <function>SPI_execute()</> (Heikki)
2873 This is used when a command is rewritten to another type of
2880 Remove unnecessary inclusions from <filename>executor/spi.h</> (Tom)
2884 SPI-using modules might need to add some <literal>#include</>
2885 lines if they were depending on <filename>spi.h</> to include
2897 <title>Build Options</title>
2902 Update build system to use <productname>Autoconf</> 2.61 (Peter)
2908 Require <productname>GNU bison</> for source code builds (Peter)
2912 This has effectively been required for several years, but now there
2913 is no infrastructure claiming to support other parser tools.
2919 Add <application>pg_config</> <literal>--htmldir</> option
2926 Pass <type>float4</> by value inside the server (Zoltan
2931 Add <application>configure</> option
2932 <literal>--disable-float4-byval</> to use the old behavior.
2933 External C functions that use old-style (version 0) call convention
2934 and pass or return <type>float4</> values will be broken by this
2935 change, so you may need the <application>configure</> option if you
2936 have such functions and don't want to update them.
2942 Pass <type>float8</>, <type>int8</>, and related datatypes
2943 by value inside the server on 64-bit platforms (Zoltan Boszormenyi)
2947 Add <application>configure</> option
2948 <literal>--disable-float8-byval</> to use the old behavior.
2949 As above, this change might break old-style external C functions.
2955 Add configure options <literal>--with-segsize</>,
2956 <literal>--with-blocksize</>, <literal>--with-wal-blocksize</>,
2957 <literal>--with-wal-segsize</> (Zdenek Kotala, Tom)
2961 This simplifies build-time control over several constants that
2962 previously could only be changed by editing
2963 <filename>pg_config_manual.h</>.
2969 Allow threaded builds on <productname>Solaris</> 2.5 (Bruce)
2975 Use the system's <function>getopt_long()</> on <productname>Solaris</>
2976 (Zdenek Kotala, Tom)
2980 This makes option processing more consistent with what Solaris users
2987 Add support for the <productname>Sun Studio</> compiler on
2988 <productname>Linux</> (Julius Stroffek)
2994 Append the major version number to the backend <application>gettext</>
2995 domain, and the <literal>soname</> major version number to
2996 libraries' <application>gettext</> domain (Peter)
3000 This simplifies parallel installations of multiple versions.
3006 Add support for code coverage testing with <application>gcov</>
3013 Allow out-of-tree builds on <productname>Mingw</> and
3014 <productname>Cygwin</> (Richard Evans)
3020 Fix the use of <productname>Mingw</> as a cross-compiling source
3030 <title>Source Code</title>
3035 Support 64-bit time zone data files (Heikki)
3039 This adds support for daylight saving time (<acronym>DST</>)
3040 calculations beyond the year 2038.
3046 Deprecate use of platform's <type>time_t</> data type (Tom)
3050 Some platforms have migrated to 64-bit <type>time_t</>, some have
3051 not, and Windows can't make up its mind what it's doing. Define
3052 <type>pg_time_t</> to have the same meaning as <type>time_t</>,
3053 but always be 64 bits (unless the platform has no 64-bit integer type),
3054 and use that type in all module APIs and on-disk data formats.
3060 Fix bug in handling of the time zone database when cross-compiling
3067 Link backend object files in one step, rather than in stages
3074 Improve <application>gettext</> support to allow better translation
3081 Add message translation support to the PL languages (Alvaro, Peter)
3087 Add more <application>DTrace</> probes (Robert Lor)
3093 Enable <application>DTrace</> support on <application>Mac OS X
3094 Leopard</> and other non-Solaris platforms (Robert Lor)
3100 Simplify and standardize conversions between C strings and
3101 <type>text</> datums, by providing common functions for the purpose
3108 Clean up the <filename>include/catalog/</> header files so that
3109 frontend programs can include them without including
3110 <filename>postgres.h</>
3117 Make <type>name</> char-aligned, and suppress zero-padding of
3118 <type>name</> entries in indexes (Tom)
3124 Recover better if dynamically-loaded code executes <function>exit()</>
3131 Add a hook to let plug-ins monitor the executor (Itagaki
3138 Add a hook to allow the planner's statistics lookup behavior to
3139 be overridden (Simon Riggs)
3145 Add <function>shmem_startup_hook()</> for custom shared memory
3152 Replace the index access method <function>amgetmulti</> entry point
3153 with <function>amgetbitmap</>, and extend the API for
3154 <function>amgettuple</> to support run-time determination of
3155 operator lossiness (Heikki, Tom, Teodor)
3159 The API for GIN and GiST opclass <function>consistent</> functions
3160 has been extended as well.
3166 Add support for partial-match searches in <acronym>GIN</> indexes
3167 (Teodor Sigaev, Oleg Bartunov)
3173 Replace <structname>pg_class</> column <structfield>reltriggers</>
3174 with boolean <structfield>relhastriggers</> (Simon)
3178 Also remove unused <structname>pg_class</> columns
3179 <structfield>relukeys</>, <structfield>relfkeys</>, and
3180 <structfield>relrefs</>.
3186 Add a <structfield>relistemp</> column to <structname>pg_class</>
3187 to ease identification of temporary tables (Tom)
3193 Move platform <acronym>FAQ</>s into the main documentation
3200 Prevent parser input files from being built with any conflicts
3207 Add support for the <literal>KOI8U</> (Ukrainian) encoding
3214 Add Japanese message translations (Japan PostgreSQL Users Group)
3218 This used to be maintained as a separate project.
3224 Fix problem when setting <varname>LC_MESSAGES</> on
3225 <application>MSVC</>-built systems (Hiroshi Inoue, Hiroshi
3235 <title>Contrib</title>
3241 Add <filename>contrib/auto_explain</> to automatically run
3242 <command>EXPLAIN</> on queries exceeding a specified duration
3243 (Itagaki Takahiro, Tom)
3249 Add <filename>contrib/btree_gin</> to allow GIN indexes to
3250 handle more datatypes (Oleg, Teodor)
3256 Add <filename>contrib/citext</> to provide a case-insensitive,
3257 multibyte-aware text data type (David Wheeler)
3263 Add <filename>contrib/pg_stat_statements</> for server-wide
3264 tracking of statement execution statistics (Itagaki Takahiro)
3270 Add duration and query mode options to <filename>contrib/pgbench</>
3277 Make <filename>contrib/pgbench</> use table names
3278 <structname>pgbench_accounts</>, <structname>pgbench_branches</>,
3279 <structname>pgbench_history</>, and <structname>pgbench_tellers</>,
3280 rather than just <structname>accounts</>, <structname>branches</>,
3281 <structname>history</>, and <structname>tellers</> (Tom)
3285 This is to reduce the risk of accidentally destroying real data
3286 by running <application>pgbench</>.
3292 Fix <filename>contrib/pgstattuple</> to handle tables and
3293 indexes with over 2 billion pages (Tatsuhito Kasahara)
3299 In <filename>contrib/fuzzystrmatch</>, add a version of the
3300 Levenshtein string-distance function that allows the user to
3301 specify the costs of insertion, deletion, and substitution
3308 Make <filename>contrib/ltree</> support multibyte encodings
3315 Enable <filename>contrib/dblink</> to use connection information
3316 stored in the SQL/MED catalogs (Joe Conway)
3322 Improve <filename>contrib/dblink</>'s reporting of errors from
3323 the remote server (Joe Conway)
3329 Make <filename>contrib/dblink</> set <varname>client_encoding</>
3330 to match the local database's encoding (Joe Conway)
3334 This prevents encoding problems when communicating with a remote
3335 database that uses a different encoding.
3341 Make sure <filename>contrib/dblink</> uses a password supplied
3342 by the user, and not accidentally taken from the server's
3343 <filename>.pgpass</> file (Joe Conway)
3347 This is a minor security enhancement.
3353 Add <function>fsm_page_contents()</>
3354 to <filename>contrib/pageinspect</> (Heikki)
3360 Modify <function>get_raw_page()</> to support free space map
3361 (<filename>*_fsm</>) files. Also update
3362 <filename>contrib/pg_freespacemap</>.
3368 Add support for multibyte encodings to <filename>contrib/pg_trgm</>
3375 Rewrite <filename>contrib/intagg</> to use new
3376 functions <function>array_agg()</> and <function>unnest()</>
3383 Make <filename>contrib/pg_standby</> recover all available WAL before
3384 failover (Fujii Masao, Simon, Heikki)
3388 To make this work safely, you now need to set the new
3389 <literal>recovery_end_command</> option in <filename>recovery.conf</>
3390 to clean up the trigger file after failover. <application>pg_standby</>
3391 will no longer remove the trigger file itself.
3397 <filename>contrib/pg_standby</>'s <option>-l</> option is now a no-op,
3398 because it is unsafe to use a symlink (Simon)
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