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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <HTML ><HEAD ><TITLE >Release 9.1</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK REV="MADE" HREF="mailto:pgsql-docs@postgresql.org"><LINK REL="HOME" TITLE="PostgreSQL 9.2.24 Documentation" HREF="index.html"><LINK REL="UP" TITLE="Release Notes" HREF="release.html"><LINK REL="PREVIOUS" TITLE="Release 9.1.1" HREF="release-9-1-1.html"><LINK REL="NEXT" TITLE="Release 9.0.23" HREF="release-9-0-23.html"><LINK REL="STYLESHEET" TYPE="text/css" HREF="stylesheet.css"><META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=ISO-8859-1"><META NAME="creation" CONTENT="2017-11-06T22:43:11"></HEAD ><BODY CLASS="SECT1" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="5" ALIGN="center" VALIGN="bottom" ><A HREF="index.html" >PostgreSQL 9.2.24 Documentation</A ></TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="top" ><A TITLE="Release 9.1.1" HREF="release-9-1-1.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="10%" ALIGN="left" VALIGN="top" ><A HREF="release.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="60%" ALIGN="center" VALIGN="bottom" >Appendix E. Release Notes</TD ><TD WIDTH="20%" ALIGN="right" VALIGN="top" ><A TITLE="Release 9.0.23" HREF="release-9-0-23.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="SECT1" ><H1 CLASS="SECT1" ><A NAME="RELEASE-9-1" >E.50. Release 9.1</A ></H1 ><DIV CLASS="FORMALPARA" ><P ><B >Release date: </B >2011-09-12</P ></DIV ><DIV CLASS="SECT2" ><H2 CLASS="SECT2" ><A NAME="AEN119076" >E.50.1. Overview</A ></H2 ><P > This release shows <SPAN CLASS="PRODUCTNAME" >PostgreSQL</SPAN > moving beyond the traditional relational-database feature set with new, ground-breaking functionality that is unique to <SPAN CLASS="PRODUCTNAME" >PostgreSQL</SPAN >. The streaming replication feature introduced in release 9.0 is significantly enhanced by adding a synchronous-replication option, streaming backups, and monitoring improvements. Major enhancements include: </P ><P ></P ><UL ><LI ><P > Allow <A HREF="warm-standby.html#SYNCHRONOUS-REPLICATION" >synchronous replication</A > </P ></LI ><LI ><P > Add support for <A HREF="sql-createforeigntable.html" >foreign tables</A > </P ></LI ><LI ><P > Add per-column <A HREF="collation.html" >collation</A > support </P ></LI ><LI ><P > Add <A HREF="extend-extensions.html" >extensions</A > which simplify packaging of additions to <SPAN CLASS="PRODUCTNAME" >PostgreSQL</SPAN > </P ></LI ><LI ><P > Add a true <A HREF="transaction-iso.html#XACT-SERIALIZABLE" >serializable isolation level</A > </P ></LI ><LI ><P > Support unlogged tables using the <TT CLASS="LITERAL" >UNLOGGED</TT > option in <A HREF="sql-createtable.html" ><TT CLASS="COMMAND" >CREATE TABLE</TT ></A > </P ></LI ><LI ><P > Allow data-modification commands (<TT CLASS="COMMAND" >INSERT</TT >/<TT CLASS="COMMAND" >UPDATE</TT >/<TT CLASS="COMMAND" >DELETE</TT >) in <A HREF="queries-with.html" ><TT CLASS="LITERAL" >WITH</TT ></A > clauses </P ></LI ><LI ><P > Add nearest-neighbor (order-by-operator) searching to <A HREF="gist.html" ><ACRONYM CLASS="ACRONYM" >GiST</ACRONYM > indexes</A > </P ></LI ><LI ><P > Add a <A HREF="sql-security-label.html" ><TT CLASS="COMMAND" >SECURITY LABEL</TT ></A > command and support for <A HREF="sepgsql.html" ><ACRONYM CLASS="ACRONYM" >SELinux</ACRONYM > permissions control</A > </P ></LI ><LI ><P > Update the <A HREF="plpython.html" >PL/Python</A > server-side language </P ></LI ></UL ><P > The above items are explained in more detail in the sections below. </P ></DIV ><DIV CLASS="SECT2" ><H2 CLASS="SECT2" ><A NAME="AEN119124" >E.50.2. Migration to Version 9.1</A ></H2 ><P > A dump/restore using <SPAN CLASS="APPLICATION" >pg_dump</SPAN >, or use of <SPAN CLASS="APPLICATION" >pg_upgrade</SPAN >, is required for those wishing to migrate data from any previous release. </P ><P > Version 9.1 contains a number of changes that may affect compatibility with previous releases. Observe the following incompatibilities: </P ><DIV CLASS="SECT3" ><H3 CLASS="SECT3" ><A NAME="AEN119130" >E.50.2.1. Strings</A ></H3 ><P ></P ><UL ><LI ><P > Change the default value of <A HREF="runtime-config-compatible.html#GUC-STANDARD-CONFORMING-STRINGS" ><TT CLASS="VARNAME" >standard_conforming_strings</TT ></A > to on (Robert Haas) </P ><P > By default, backslashes are now ordinary characters in string literals, not escape characters. This change removes a long-standing incompatibility with the SQL standard. <A HREF="runtime-config-compatible.html#GUC-ESCAPE-STRING-WARNING" ><TT CLASS="VARNAME" >escape_string_warning</TT ></A > has produced warnings about this usage for years. <TT CLASS="LITERAL" >E''</TT > strings are the proper way to embed backslash escapes in strings and are unaffected by this change. </P ><DIV CLASS="WARNING" ><P ></P ><TABLE CLASS="WARNING" BORDER="1" WIDTH="90%" ><TR ><TD ALIGN="CENTER" ><B >Warning</B ></TD ></TR ><TR ><TD ALIGN="LEFT" ><P > This change can break applications that are not expecting it and do their own string escaping according to the old rules. The consequences could be as severe as introducing SQL-injection security holes. Be sure to test applications that are exposed to untrusted input, to ensure that they correctly handle single quotes and backslashes in text strings. </P ></TD ></TR ></TABLE ></DIV ></LI ></UL ></DIV ><DIV CLASS="SECT3" ><H3 CLASS="SECT3" ><A NAME="AEN119143" >E.50.2.2. Casting</A ></H3 ><P ></P ><UL ><LI ><P > Disallow function-style and attribute-style data type casts for composite types (Tom Lane) </P ><P > For example, disallow <TT CLASS="LITERAL" ><TT CLASS="REPLACEABLE" ><I >composite_value</I ></TT >.text</TT > and <TT CLASS="LITERAL" >text(<TT CLASS="REPLACEABLE" ><I >composite_value</I ></TT >)</TT >. Unintentional uses of this syntax have frequently resulted in bug reports; although it was not a bug, it seems better to go back to rejecting such expressions. The <TT CLASS="LITERAL" >CAST</TT > and <TT CLASS="LITERAL" >::</TT > syntaxes are still available for use when a cast of an entire composite value is actually intended. </P ></LI ><LI ><P > Tighten casting checks for domains based on arrays (Tom Lane) </P ><P > When a domain is based on an array type, it is allowed to <SPAN CLASS="QUOTE" >"look through"</SPAN > the domain type to access the array elements, including subscripting the domain value to fetch or assign an element. Assignment to an element of such a domain value, for instance via <TT CLASS="LITERAL" >UPDATE ... SET domaincol[5] = ...</TT >, will now result in rechecking the domain type's constraints, whereas before the checks were skipped. </P ></LI ></UL ></DIV ><DIV CLASS="SECT3" ><H3 CLASS="SECT3" ><A NAME="AEN119160" >E.50.2.3. Arrays</A ></H3 ><P ></P ><UL ><LI ><P > Change <A HREF="functions-array.html#ARRAY-FUNCTIONS-TABLE" ><CODE CLASS="FUNCTION" >string_to_array()</CODE ></A > to return an empty array for a zero-length string (Pavel Stehule) </P ><P > Previously this returned a null value. </P ></LI ><LI ><P > Change <A HREF="functions-array.html#ARRAY-FUNCTIONS-TABLE" ><CODE CLASS="FUNCTION" >string_to_array()</CODE ></A > so a <TT CLASS="LITERAL" >NULL</TT > separator splits the string into characters (Pavel Stehule) </P ><P > Previously this returned a null value. </P ></LI ></UL ></DIV ><DIV CLASS="SECT3" ><H3 CLASS="SECT3" ><A NAME="AEN119174" >E.50.2.4. Object Modification</A ></H3 ><P ></P ><UL ><LI ><P > Fix improper checks for before/after triggers (Tom Lane) </P ><P > Triggers can now be fired in three cases: <TT CLASS="LITERAL" >BEFORE</TT >, <TT CLASS="LITERAL" >AFTER</TT >, or <TT CLASS="LITERAL" >INSTEAD OF</TT > some action. Trigger function authors should verify that their logic behaves sanely in all three cases. </P ></LI ><LI ><P > Require superuser or <TT CLASS="LITERAL" >CREATEROLE</TT > permissions in order to set comments on roles (Tom Lane) </P ></LI ></UL ></DIV ><DIV CLASS="SECT3" ><H3 CLASS="SECT3" ><A NAME="AEN119186" >E.50.2.5. Server Settings</A ></H3 ><P ></P ><UL ><LI ><P > Change <A HREF="functions-admin.html#FUNCTIONS-RECOVERY-INFO-TABLE" ><CODE CLASS="FUNCTION" >pg_last_xlog_receive_location()</CODE ></A > so it never moves backwards (Fujii Masao) </P ><P > Previously, the value of <CODE CLASS="FUNCTION" >pg_last_xlog_receive_location()</CODE > could move backward when streaming replication is restarted. </P ></LI ><LI ><P > Have logging of replication connections honor <A HREF="runtime-config-logging.html#GUC-LOG-CONNECTIONS" ><TT CLASS="VARNAME" >log_connections</TT ></A > (Magnus Hagander) </P ><P > Previously, replication connections were always logged. </P ></LI ></UL ></DIV ><DIV CLASS="SECT3" ><H3 CLASS="SECT3" ><A NAME="AEN119200" >E.50.2.6. <A HREF="plpgsql.html" >PL/pgSQL</A > Server-Side Language</A ></H3 ><P ></P ><UL ><LI ><P > Change PL/pgSQL's <TT CLASS="LITERAL" >RAISE</TT > command without parameters to be catchable by the attached exception block (Piyush Newe) </P ><P > Previously <TT CLASS="LITERAL" >RAISE</TT > in a code block was always scoped to an attached exception block, so it was uncatchable at the same scope. </P ></LI ><LI ><P > Adjust PL/pgSQL's error line numbering code to be consistent with other PLs (Pavel Stehule) </P ><P > Previously, PL/pgSQL would ignore (not count) an empty line at the start of the function body. Since this was inconsistent with all other languages, the special case was removed. </P ></LI ><LI ><P > Make PL/pgSQL complain about conflicting IN and OUT parameter names (Tom Lane) </P ><P > Formerly, the collision was not detected, and the name would just silently refer to only the OUT parameter. </P ></LI ><LI ><P > Type modifiers of PL/pgSQL variables are now visible to the SQL parser (Tom Lane) </P ><P > A type modifier (such as a varchar length limit) attached to a PL/pgSQL variable was formerly enforced during assignments, but was ignored for all other purposes. Such variables will now behave more like table columns declared with the same modifier. This is not expected to make any visible difference in most cases, but it could result in subtle changes for some SQL commands issued by PL/pgSQL functions. </P ></LI ></UL ></DIV ><DIV CLASS="SECT3" ><H3 CLASS="SECT3" ><A NAME="AEN119218" >E.50.2.7. Contrib</A ></H3 ><P ></P ><UL ><LI ><P > All contrib modules are now installed with <A HREF="sql-createextension.html" ><TT CLASS="COMMAND" >CREATE EXTENSION</TT ></A > rather than by manually invoking their SQL scripts (Dimitri Fontaine, Tom Lane) </P ><P > To update an existing database containing the 9.0 version of a contrib module, use <TT CLASS="LITERAL" >CREATE EXTENSION ... FROM unpackaged</TT > to wrap the existing contrib module's objects into an extension. When updating from a pre-9.0 version, drop the contrib module's objects using its old uninstall script, then use <TT CLASS="LITERAL" >CREATE EXTENSION</TT >. </P ></LI ></UL ></DIV ><DIV CLASS="SECT3" ><H3 CLASS="SECT3" ><A NAME="AEN119228" >E.50.2.8. Other Incompatibilities</A ></H3 ><P ></P ><UL ><LI ><P > Make <A HREF="monitoring-stats.html#MONITORING-STATS-FUNCS-TABLE" ><CODE CLASS="FUNCTION" >pg_stat_reset()</CODE ></A > reset all database-level statistics (Tomas Vondra) </P ><P > Some <TT CLASS="STRUCTNAME" >pg_stat_database</TT > counters were not being reset. </P ></LI ><LI ><P > Fix some <A HREF="infoschema-triggers.html" ><TT CLASS="STRUCTNAME" >information_schema.triggers</TT ></A > column names to match the new SQL-standard names (Dean Rasheed) </P ></LI ><LI ><P > Treat <SPAN CLASS="APPLICATION" >ECPG</SPAN > cursor names as case-insensitive (Zoltan Boszormenyi) </P ></LI ></UL ></DIV ></DIV ><DIV CLASS="SECT2" ><H2 CLASS="SECT2" ><A NAME="AEN119244" >E.50.3. Changes</A ></H2 ><P > Below you will find a detailed account of the changes between <SPAN CLASS="PRODUCTNAME" >PostgreSQL</SPAN > 9.1 and the previous major release. </P ><DIV CLASS="SECT3" ><H3 CLASS="SECT3" ><A NAME="AEN119248" >E.50.3.1. Server</A ></H3 ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119250" >E.50.3.1.1. Performance</A ></H4 ><P ></P ><UL ><LI ><P > Support unlogged tables using the <TT CLASS="LITERAL" >UNLOGGED</TT > option in <A HREF="sql-createtable.html" ><TT CLASS="COMMAND" >CREATE TABLE</TT ></A > (Robert Haas) </P ><P > Such tables provide better update performance than regular tables, but are not crash-safe: their contents are automatically cleared in case of a server crash. Their contents do not propagate to replication slaves, either. </P ></LI ><LI ><P > Allow <TT CLASS="LITERAL" >FULL OUTER JOIN</TT > to be implemented as a hash join, and allow either side of a <TT CLASS="LITERAL" >LEFT OUTER JOIN</TT > or <TT CLASS="LITERAL" >RIGHT OUTER JOIN</TT > to be hashed (Tom Lane) </P ><P > Previously <TT CLASS="LITERAL" >FULL OUTER JOIN</TT > could only be implemented as a merge join, and <TT CLASS="LITERAL" >LEFT OUTER JOIN</TT > and <TT CLASS="LITERAL" >RIGHT OUTER JOIN</TT > could hash only the nullable side of the join. These changes provide additional query optimization possibilities. </P ></LI ><LI ><P > Merge duplicate fsync requests (Robert Haas, Greg Smith) </P ><P > This greatly improves performance under heavy write loads. </P ></LI ><LI ><P > Improve performance of <A HREF="runtime-config-wal.html#GUC-COMMIT-SIBLINGS" ><TT CLASS="VARNAME" >commit_siblings</TT ></A > (Greg Smith) </P ><P > This allows the use of <TT CLASS="VARNAME" >commit_siblings</TT > with less overhead. </P ></LI ><LI ><P > Reduce the memory requirement for large ispell dictionaries (Pavel Stehule, Tom Lane) </P ></LI ><LI ><P > Avoid leaving data files open after <SPAN CLASS="QUOTE" >"blind writes"</SPAN > (Alvaro Herrera) </P ><P > This fixes scenarios in which backends might hold files open long after they were deleted, preventing the kernel from reclaiming disk space. </P ></LI ></UL ></DIV ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119283" >E.50.3.1.2. Optimizer</A ></H4 ><P ></P ><UL ><LI ><P > Allow inheritance table scans to return meaningfully-sorted results (Greg Stark, Hans-Jurgen Schonig, Robert Haas, Tom Lane) </P ><P > This allows better optimization of queries that use <TT CLASS="LITERAL" >ORDER BY</TT >, <TT CLASS="LITERAL" >LIMIT</TT >, or <TT CLASS="LITERAL" >MIN</TT >/<TT CLASS="LITERAL" >MAX</TT > with inherited tables. </P ></LI ><LI ><P > Improve GIN index scan cost estimation (Teodor Sigaev) </P ></LI ><LI ><P > Improve cost estimation for aggregates and window functions (Tom Lane) </P ></LI ></UL ></DIV ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119297" >E.50.3.1.3. Authentication</A ></H4 ><P ></P ><UL ><LI ><P > Support host names and host suffixes (e.g. <TT CLASS="LITERAL" >.example.com</TT >) in <A HREF="auth-pg-hba-conf.html" ><TT CLASS="FILENAME" >pg_hba.conf</TT ></A > (Peter Eisentraut) </P ><P > Previously only host <ACRONYM CLASS="ACRONYM" >IP</ACRONYM > addresses and <ACRONYM CLASS="ACRONYM" >CIDR</ACRONYM > values were supported. </P ></LI ><LI ><P > Support the key word <TT CLASS="LITERAL" >all</TT > in the host column of <A HREF="auth-pg-hba-conf.html" ><TT CLASS="FILENAME" >pg_hba.conf</TT ></A > (Peter Eisentraut) </P ><P > Previously people used <TT CLASS="LITERAL" >0.0.0.0/0</TT > or <TT CLASS="LITERAL" >::/0</TT > for this. </P ></LI ><LI ><P > Reject <TT CLASS="LITERAL" >local</TT > lines in <A HREF="auth-pg-hba-conf.html" ><TT CLASS="FILENAME" >pg_hba.conf</TT ></A > on platforms that don't support Unix-socket connections (Magnus Hagander) </P ><P > Formerly, such lines were silently ignored, which could be surprising. This makes the behavior more like other unsupported cases. </P ></LI ><LI ><P > Allow <A HREF="auth-methods.html#GSSAPI-AUTH" ><ACRONYM CLASS="ACRONYM" >GSSAPI</ACRONYM ></A > to be used to authenticate to servers via <A HREF="auth-methods.html#SSPI-AUTH" ><ACRONYM CLASS="ACRONYM" >SSPI</ACRONYM ></A > (Christian Ullrich) </P ><P > Specifically this allows Unix-based <ACRONYM CLASS="ACRONYM" >GSSAPI</ACRONYM > clients to do <ACRONYM CLASS="ACRONYM" >SSPI</ACRONYM > authentication with Windows servers. </P ></LI ><LI ><P > <A HREF="auth-methods.html#AUTH-IDENT" ><TT CLASS="LITERAL" >ident</TT ></A > authentication over local sockets is now known as <A HREF="auth-methods.html#AUTH-PEER" ><TT CLASS="LITERAL" >peer</TT ></A > (Magnus Hagander) </P ><P > The old term is still accepted for backward compatibility, but since the two methods are fundamentally different, it seemed better to adopt different names for them. </P ></LI ><LI ><P > Rewrite <A HREF="auth-methods.html#AUTH-PEER" ><ACRONYM CLASS="ACRONYM" >peer</ACRONYM ></A > authentication to avoid use of credential control messages (Tom Lane) </P ><P > This change makes the peer authentication code simpler and better-performing. However, it requires the platform to provide the <CODE CLASS="FUNCTION" >getpeereid</CODE > function or an equivalent socket operation. So far as is known, the only platform for which peer authentication worked before and now will not is pre-5.0 NetBSD. </P ></LI ></UL ></DIV ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119344" >E.50.3.1.4. Monitoring</A ></H4 ><P ></P ><UL ><LI ><P > Add details to the logging of restartpoints and checkpoints, which is controlled by <A HREF="runtime-config-logging.html#GUC-LOG-CHECKPOINTS" ><TT CLASS="VARNAME" >log_checkpoints</TT ></A > (Fujii Masao, Greg Smith) </P ><P > New details include <ACRONYM CLASS="ACRONYM" >WAL</ACRONYM > file and sync activity. </P ></LI ><LI ><P > Add <A HREF="runtime-config-logging.html#GUC-LOG-FILE-MODE" ><TT CLASS="VARNAME" >log_file_mode</TT ></A > which controls the permissions on log files created by the logging collector (Martin Pihlak) </P ></LI ><LI ><P > Reduce the default maximum line length for <SPAN CLASS="APPLICATION" >syslog</SPAN > logging to 900 bytes plus prefixes (Noah Misch) </P ><P > This avoids truncation of long log lines on syslog implementations that have a 1KB length limit, rather than the more common 2KB. </P ></LI ></UL ></DIV ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119361" >E.50.3.1.5. Statistical Views</A ></H4 ><P ></P ><UL ><LI ><P > Add <TT CLASS="STRUCTFIELD" >client_hostname</TT > column to <A HREF="monitoring-stats.html#MONITORING-STATS-VIEWS-TABLE" ><TT CLASS="STRUCTNAME" >pg_stat_activity</TT ></A > (Peter Eisentraut) </P ><P > Previously only the client address was reported. </P ></LI ><LI ><P > Add <A HREF="monitoring-stats.html#MONITORING-STATS-VIEWS-TABLE" ><TT CLASS="STRUCTNAME" >pg_stat_xact_*</TT ></A > statistics functions and views (Joel Jacobson) </P ><P > These are like the database-wide statistics counter views, but reflect counts for only the current transaction. </P ></LI ><LI ><P > Add time of last reset in database-level and background writer statistics views (Tomas Vondra) </P ></LI ><LI ><P > Add columns showing the number of vacuum and analyze operations in <A HREF="monitoring-stats.html#MONITORING-STATS-VIEWS-TABLE" ><TT CLASS="STRUCTNAME" >pg_stat_*_tables</TT ></A > views (Magnus Hagander) </P ></LI ><LI ><P > Add <TT CLASS="STRUCTFIELD" >buffers_backend_fsync</TT > column to <A HREF="monitoring-stats.html#MONITORING-STATS-VIEWS-TABLE" ><TT CLASS="STRUCTNAME" >pg_stat_bgwriter</TT ></A > (Greg Smith) </P ><P > This new column counts the number of times a backend fsyncs a buffer. </P ></LI ></UL ></DIV ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119387" >E.50.3.1.6. Server Settings</A ></H4 ><P ></P ><UL ><LI ><P > Provide auto-tuning of <A HREF="runtime-config-wal.html#GUC-WAL-BUFFERS" ><TT CLASS="VARNAME" >wal_buffers</TT ></A > (Greg Smith) </P ><P > By default, the value of <TT CLASS="VARNAME" >wal_buffers</TT > is now chosen automatically based on the value of <TT CLASS="VARNAME" >shared_buffers</TT >. </P ></LI ><LI ><P > Increase the maximum values for <A HREF="runtime-config-locks.html#GUC-DEADLOCK-TIMEOUT" ><TT CLASS="VARNAME" >deadlock_timeout</TT ></A >, <A HREF="runtime-config-logging.html#GUC-LOG-MIN-DURATION-STATEMENT" ><TT CLASS="VARNAME" >log_min_duration_statement</TT ></A >, and <A HREF="runtime-config-autovacuum.html#GUC-LOG-AUTOVACUUM-MIN-DURATION" ><TT CLASS="VARNAME" >log_autovacuum_min_duration</TT ></A > (Peter Eisentraut) </P ><P > The maximum value for each of these parameters was previously only about 35 minutes. Much larger values are now allowed. </P ></LI ></UL ></DIV ></DIV ><DIV CLASS="SECT3" ><H3 CLASS="SECT3" ><A NAME="AEN119406" >E.50.3.2. Replication and Recovery</A ></H3 ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119408" >E.50.3.2.1. Streaming Replication and Continuous Archiving</A ></H4 ><P ></P ><UL ><LI ><P > Allow <A HREF="warm-standby.html#SYNCHRONOUS-REPLICATION" >synchronous replication</A > (Simon Riggs, Fujii Masao) </P ><P > This allows the primary server to wait for a standby to write a transaction's information to disk before acknowledging the commit. One standby at a time can take the role of the synchronous standby, as controlled by the <A HREF="runtime-config-replication.html#GUC-SYNCHRONOUS-STANDBY-NAMES" ><TT CLASS="VARNAME" >synchronous_standby_names</TT ></A > setting. Synchronous replication can be enabled or disabled on a per-transaction basis using the <A HREF="runtime-config-wal.html#GUC-SYNCHRONOUS-COMMIT" ><TT CLASS="VARNAME" >synchronous_commit</TT ></A > setting. </P ></LI ><LI ><P > Add protocol support for sending file system backups to standby servers using the streaming replication network connection (Magnus Hagander, Heikki Linnakangas) </P ><P > This avoids the requirement of manually transferring a file system backup when setting up a standby server. </P ></LI ><LI ><P > Add <TT CLASS="VARNAME" >replication_timeout</TT > setting (Fujii Masao, Heikki Linnakangas) </P ><P > Replication connections that are idle for more than the <TT CLASS="VARNAME" >replication_timeout</TT > interval will be terminated automatically. Formerly, a failed connection was typically not detected until the TCP timeout elapsed, which is inconveniently long in many situations. </P ></LI ><LI ><P > Add command-line tool <A HREF="app-pgbasebackup.html" ><SPAN CLASS="APPLICATION" >pg_basebackup</SPAN ></A > for creating a new standby server or database backup (Magnus Hagander) </P ></LI ><LI ><P > Add a <A HREF="sql-createrole.html" >replication permission</A > for roles (Magnus Hagander) </P ><P > This is a read-only permission used for streaming replication. It allows a non-superuser role to be used for replication connections. Previously only superusers could initiate replication connections; superusers still have this permission by default. </P ></LI ></UL ></DIV ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119435" >E.50.3.2.2. Replication Monitoring</A ></H4 ><P ></P ><UL ><LI ><P > Add system view <A HREF="monitoring-stats.html#MONITORING-STATS-VIEWS-TABLE" ><TT CLASS="STRUCTNAME" >pg_stat_replication</TT ></A > which displays activity of <ACRONYM CLASS="ACRONYM" >WAL</ACRONYM > sender processes (Itagaki Takahiro, Simon Riggs) </P ><P > This reports the status of all connected standby servers. </P ></LI ><LI ><P > Add monitoring function <A HREF="functions-admin.html#FUNCTIONS-RECOVERY-INFO-TABLE" ><CODE CLASS="FUNCTION" >pg_last_xact_replay_timestamp()</CODE ></A > (Fujii Masao) </P ><P > This returns the time at which the primary generated the most recent commit or abort record applied on the standby. </P ></LI ></UL ></DIV ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119449" >E.50.3.2.3. Hot Standby</A ></H4 ><P ></P ><UL ><LI ><P > Add configuration parameter <A HREF="runtime-config-replication.html#GUC-HOT-STANDBY-FEEDBACK" ><TT CLASS="VARNAME" >hot_standby_feedback</TT ></A > to enable standbys to postpone cleanup of old row versions on the primary (Simon Riggs) </P ><P > This helps avoid canceling long-running queries on the standby. </P ></LI ><LI ><P > Add the <A HREF="monitoring-stats.html#MONITORING-STATS-VIEWS-TABLE" ><TT CLASS="STRUCTNAME" >pg_stat_database_conflicts</TT ></A > system view to show queries that have been canceled and the reason (Magnus Hagander) </P ><P > Cancellations can occur because of dropped tablespaces, lock timeouts, old snapshots, pinned buffers, and deadlocks. </P ></LI ><LI ><P > Add a <TT CLASS="STRUCTFIELD" >conflicts</TT > count to <A HREF="monitoring-stats.html#MONITORING-STATS-VIEWS-TABLE" ><TT CLASS="STRUCTNAME" >pg_stat_database</TT ></A > (Magnus Hagander) </P ><P > This is the number of conflicts that occurred in the database. </P ></LI ><LI ><P > Increase the maximum values for <A HREF="runtime-config-replication.html#GUC-MAX-STANDBY-ARCHIVE-DELAY" ><TT CLASS="VARNAME" >max_standby_archive_delay</TT ></A > and <A HREF="runtime-config-replication.html#GUC-MAX-STANDBY-STREAMING-DELAY" ><TT CLASS="VARNAME" >max_standby_streaming_delay</TT ></A > </P ><P > The maximum value for each of these parameters was previously only about 35 minutes. Much larger values are now allowed. </P ></LI ><LI ><P > Add <A HREF="errcodes-appendix.html#ERRCODES-TABLE" ><TT CLASS="LITERAL" >ERRCODE_T_R_DATABASE_DROPPED</TT ></A > error code to report recovery conflicts due to dropped databases (Tatsuo Ishii) </P ><P > This is useful for connection pooling software. </P ></LI ></UL ></DIV ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119480" >E.50.3.2.4. Recovery Control</A ></H4 ><P ></P ><UL ><LI ><P > Add functions to control streaming replication replay (Simon Riggs) </P ><P > The new functions are <A HREF="functions-admin.html#FUNCTIONS-RECOVERY-CONTROL-TABLE" ><CODE CLASS="FUNCTION" >pg_xlog_replay_pause()</CODE ></A >, <A HREF="functions-admin.html#FUNCTIONS-RECOVERY-CONTROL-TABLE" ><CODE CLASS="FUNCTION" >pg_xlog_replay_resume()</CODE ></A >, and the status function <A HREF="functions-admin.html#FUNCTIONS-RECOVERY-CONTROL-TABLE" ><CODE CLASS="FUNCTION" >pg_is_xlog_replay_paused()</CODE ></A >. </P ></LI ><LI ><P > Add <TT CLASS="FILENAME" >recovery.conf</TT > setting <TT CLASS="VARNAME" >pause_at_recovery_target</TT > to pause recovery at target (Simon Riggs) </P ><P > This allows a recovery server to be queried to check whether the recovery point is the one desired. </P ></LI ><LI ><P > Add the ability to create named restore points using <A HREF="functions-admin.html#FUNCTIONS-ADMIN-BACKUP-TABLE" ><CODE CLASS="FUNCTION" >pg_create_restore_point()</CODE ></A > (Jaime Casanova) </P ><P > These named restore points can be specified as recovery targets using the new <TT CLASS="FILENAME" >recovery.conf</TT > setting <A HREF="recovery-target-settings.html#RECOVERY-TARGET-NAME" ><TT CLASS="VARNAME" >recovery_target_name</TT ></A >. </P ></LI ><LI ><P > Allow standby recovery to switch to a new timeline automatically (Heikki Linnakangas) </P ><P > Now standby servers scan the archive directory for new timelines periodically. </P ></LI ><LI ><P > Add <A HREF="runtime-config-error-handling.html#GUC-RESTART-AFTER-CRASH" ><TT CLASS="VARNAME" >restart_after_crash</TT ></A > setting which disables automatic server restart after a backend crash (Robert Haas) </P ><P > This allows external cluster management software to control whether the database server restarts or not. </P ></LI ><LI ><P > Allow <A HREF="recovery-config.html" ><TT CLASS="FILENAME" >recovery.conf</TT ></A > to use the same quoting behavior as <TT CLASS="FILENAME" >postgresql.conf</TT > (Dimitri Fontaine) </P ><P > Previously all values had to be quoted. </P ></LI ></UL ></DIV ></DIV ><DIV CLASS="SECT3" ><H3 CLASS="SECT3" ><A NAME="AEN119519" >E.50.3.3. Queries</A ></H3 ><P ></P ><UL ><LI ><P > Add a true <A HREF="transaction-iso.html#XACT-SERIALIZABLE" >serializable isolation level</A > (Kevin Grittner, Dan Ports) </P ><P > Previously, asking for serializable isolation guaranteed only that a single MVCC snapshot would be used for the entire transaction, which allowed certain documented anomalies. The old snapshot isolation behavior is still available by requesting the <A HREF="transaction-iso.html#XACT-REPEATABLE-READ" ><TT CLASS="LITERAL" >REPEATABLE READ</TT ></A > isolation level. </P ></LI ><LI ><P > Allow data-modification commands (<TT CLASS="COMMAND" >INSERT</TT >/<TT CLASS="COMMAND" >UPDATE</TT >/<TT CLASS="COMMAND" >DELETE</TT >) in <A HREF="queries-with.html" ><TT CLASS="LITERAL" >WITH</TT ></A > clauses (Marko Tiikkaja, Hitoshi Harada) </P ><P > These commands can use <TT CLASS="LITERAL" >RETURNING</TT > to pass data up to the containing query. </P ></LI ><LI ><P > Allow <A HREF="queries-with.html" ><TT CLASS="LITERAL" >WITH</TT ></A > clauses to be attached to <TT CLASS="COMMAND" >INSERT</TT >, <TT CLASS="COMMAND" >UPDATE</TT >, <TT CLASS="COMMAND" >DELETE</TT > statements (Marko Tiikkaja, Hitoshi Harada) </P ></LI ><LI ><P > Allow non-<A HREF="queries-table-expressions.html#QUERIES-GROUP" ><TT CLASS="LITERAL" >GROUP BY</TT ></A > columns in the query target list when the primary key is specified in the <TT CLASS="LITERAL" >GROUP BY</TT > clause (Peter Eisentraut) </P ><P > The SQL standard allows this behavior, and because of the primary key, the result is unambiguous. </P ></LI ><LI ><P > Allow use of the key word <TT CLASS="LITERAL" >DISTINCT</TT > in <A HREF="queries-union.html" ><TT CLASS="LITERAL" >UNION</TT >/<TT CLASS="LITERAL" >INTERSECT</TT >/<TT CLASS="LITERAL" >EXCEPT</TT ></A > clauses (Tom Lane) </P ><P > <TT CLASS="LITERAL" >DISTINCT</TT > is the default behavior so use of this key word is redundant, but the SQL standard allows it. </P ></LI ><LI ><P > Fix ordinary queries with rules to use the same snapshot behavior as <TT CLASS="COMMAND" >EXPLAIN ANALYZE</TT > (Marko Tiikkaja) </P ><P > Previously <TT CLASS="COMMAND" >EXPLAIN ANALYZE</TT > used slightly different snapshot timing for queries involving rules. The <TT CLASS="COMMAND" >EXPLAIN ANALYZE</TT > behavior was judged to be more logical. </P ></LI ></UL ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119565" >E.50.3.3.1. Strings</A ></H4 ><P ></P ><UL ><LI ><P > Add per-column <A HREF="collation.html" >collation</A > support (Peter Eisentraut, Tom Lane) </P ><P > Previously collation (the sort ordering of text strings) could only be chosen at database creation. Collation can now be set per column, domain, index, or expression, via the SQL-standard <TT CLASS="LITERAL" >COLLATE</TT > clause. </P ></LI ></UL ></DIV ></DIV ><DIV CLASS="SECT3" ><H3 CLASS="SECT3" ><A NAME="AEN119573" >E.50.3.4. Object Manipulation</A ></H3 ><P ></P ><UL ><LI ><P > Add <A HREF="extend-extensions.html" >extensions</A > which simplify packaging of additions to <SPAN CLASS="PRODUCTNAME" >PostgreSQL</SPAN > (Dimitri Fontaine, Tom Lane) </P ><P > Extensions are controlled by the new <A HREF="sql-createextension.html" ><TT CLASS="COMMAND" >CREATE</TT ></A >/<A HREF="sql-alterextension.html" ><TT CLASS="COMMAND" >ALTER</TT ></A >/<A HREF="sql-dropextension.html" ><TT CLASS="COMMAND" >DROP EXTENSION</TT ></A > commands. This replaces ad-hoc methods of grouping objects that are added to a <SPAN CLASS="PRODUCTNAME" >PostgreSQL</SPAN > installation. </P ></LI ><LI ><P > Add support for <A HREF="sql-createforeigntable.html" >foreign tables</A > (Shigeru Hanada, Robert Haas, Jan Urbanski, Heikki Linnakangas) </P ><P > This allows data stored outside the database to be used like native <SPAN CLASS="PRODUCTNAME" >PostgreSQL</SPAN >-stored data. Foreign tables are currently read-only, however. </P ></LI ><LI ><P > Allow new values to be added to an existing enum type via <A HREF="sql-altertype.html" ><TT CLASS="COMMAND" >ALTER TYPE</TT ></A > (Andrew Dunstan) </P ></LI ><LI ><P > Add <A HREF="sql-altertype.html" ><TT CLASS="COMMAND" >ALTER TYPE ... ADD/DROP/ALTER/RENAME ATTRIBUTE</TT ></A > (Peter Eisentraut) </P ><P > This allows modification of composite types. </P ></LI ></UL ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119602" >E.50.3.4.1. <TT CLASS="COMMAND" >ALTER</TT > Object</A ></H4 ><P ></P ><UL ><LI ><P > Add <TT CLASS="LITERAL" >RESTRICT</TT >/<TT CLASS="LITERAL" >CASCADE</TT > to <A HREF="sql-altertype.html" ><TT CLASS="COMMAND" >ALTER TYPE</TT ></A > operations on typed tables (Peter Eisentraut) </P ><P > This controls <TT CLASS="LITERAL" >ADD</TT >/<TT CLASS="LITERAL" >DROP</TT >/<TT CLASS="LITERAL" >ALTER</TT >/<TT CLASS="LITERAL" >RENAME ATTRIBUTE</TT > cascading behavior. </P ></LI ><LI ><P > Support <TT CLASS="LITERAL" >ALTER TABLE <TT CLASS="REPLACEABLE" ><I >name</I ></TT > {OF | NOT OF} <TT CLASS="REPLACEABLE" ><I >type</I ></TT ></TT > (Noah Misch) </P ><P > This syntax allows a standalone table to be made into a typed table, or a typed table to be made standalone. </P ></LI ><LI ><P > Add support for more object types in <TT CLASS="COMMAND" >ALTER ... SET SCHEMA</TT > commands (Dimitri Fontaine) </P ><P > This command is now supported for conversions, operators, operator classes, operator families, text search configurations, text search dictionaries, text search parsers, and text search templates. </P ></LI ></UL ></DIV ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119627" >E.50.3.4.2. <A HREF="sql-createtable.html" ><TT CLASS="COMMAND" >CREATE/ALTER TABLE</TT ></A ></A ></H4 ><P ></P ><UL ><LI ><P > Add <TT CLASS="COMMAND" >ALTER TABLE ... ADD UNIQUE/PRIMARY KEY USING INDEX</TT > (Gurjeet Singh) </P ><P > This allows a primary key or unique constraint to be defined using an existing unique index, including a concurrently created unique index. </P ></LI ><LI ><P > Allow <TT CLASS="COMMAND" >ALTER TABLE</TT > to add foreign keys without validation (Simon Riggs) </P ><P > The new option is called <TT CLASS="LITERAL" >NOT VALID</TT >. The constraint's state can later be modified to <TT CLASS="LITERAL" >VALIDATED</TT > and validation checks performed. Together these allow you to add a foreign key with minimal impact on read and write operations. </P ></LI ><LI ><P > Allow <A HREF="sql-altertable.html" ><TT CLASS="COMMAND" >ALTER TABLE ... SET DATA TYPE</TT ></A > to avoid table rewrites in appropriate cases (Noah Misch, Robert Haas) </P ><P > For example, converting a <TT CLASS="TYPE" >varchar</TT > column to <TT CLASS="TYPE" >text</TT > no longer requires a rewrite of the table. However, increasing the length constraint on a <TT CLASS="TYPE" >varchar</TT > column still requires a table rewrite. </P ></LI ><LI ><P > Add <A HREF="sql-createtable.html" ><TT CLASS="COMMAND" >CREATE TABLE IF NOT EXISTS</TT ></A > syntax (Robert Haas) </P ><P > This allows table creation without causing an error if the table already exists. </P ></LI ><LI ><P > Fix possible <SPAN CLASS="QUOTE" >"tuple concurrently updated"</SPAN > error when two backends attempt to add an inheritance child to the same table at the same time (Robert Haas) </P ><P > <A HREF="sql-altertable.html" ><TT CLASS="COMMAND" >ALTER TABLE</TT ></A > now takes a stronger lock on the parent table, so that the sessions cannot try to update it simultaneously. </P ></LI ></UL ></DIV ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119661" >E.50.3.4.3. Object Permissions</A ></H4 ><P ></P ><UL ><LI ><P > Add a <A HREF="sql-security-label.html" ><TT CLASS="COMMAND" >SECURITY LABEL</TT ></A > command (KaiGai Kohei) </P ><P > This allows security labels to be assigned to objects. </P ></LI ></UL ></DIV ></DIV ><DIV CLASS="SECT3" ><H3 CLASS="SECT3" ><A NAME="AEN119669" >E.50.3.5. Utility Operations</A ></H3 ><P ></P ><UL ><LI ><P > Add transaction-level <A HREF="explicit-locking.html#ADVISORY-LOCKS" >advisory locks</A > (Marko Tiikkaja) </P ><P > These are similar to the existing session-level advisory locks, but such locks are automatically released at transaction end. </P ></LI ><LI ><P > Make <A HREF="sql-truncate.html" ><TT CLASS="COMMAND" >TRUNCATE ... RESTART IDENTITY</TT ></A > restart sequences transactionally (Steve Singer) </P ><P > Previously the counter could have been left out of sync if a backend crashed between the on-commit truncation activity and commit completion. </P ></LI ></UL ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119681" >E.50.3.5.1. <A HREF="sql-copy.html" ><TT CLASS="COMMAND" >COPY</TT ></A ></A ></H4 ><P ></P ><UL ><LI ><P > Add <TT CLASS="LITERAL" >ENCODING</TT > option to <A HREF="sql-copy.html" ><TT CLASS="COMMAND" >COPY TO/FROM</TT ></A > (Hitoshi Harada, Itagaki Takahiro) </P ><P > This allows the encoding of the <TT CLASS="COMMAND" >COPY</TT > file to be specified separately from client encoding. </P ></LI ><LI ><P > Add bidirectional <A HREF="sql-copy.html" ><TT CLASS="COMMAND" >COPY</TT ></A > protocol support (Fujii Masao) </P ><P > This is currently only used by streaming replication. </P ></LI ></UL ></DIV ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119698" >E.50.3.5.2. <A HREF="sql-explain.html" ><TT CLASS="COMMAND" >EXPLAIN</TT ></A ></A ></H4 ><P ></P ><UL ><LI ><P > Make <TT CLASS="COMMAND" >EXPLAIN VERBOSE</TT > show the function call expression in a <TT CLASS="LITERAL" >FunctionScan</TT > node (Tom Lane) </P ></LI ></UL ></DIV ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119707" >E.50.3.5.3. <A HREF="sql-vacuum.html" ><TT CLASS="COMMAND" >VACUUM</TT ></A ></A ></H4 ><P ></P ><UL ><LI ><P > Add additional details to the output of <A HREF="sql-vacuum.html" ><TT CLASS="COMMAND" >VACUUM FULL VERBOSE</TT ></A > and <A HREF="sql-cluster.html" ><TT CLASS="COMMAND" >CLUSTER VERBOSE</TT ></A > (Itagaki Takahiro) </P ><P > New information includes the live and dead tuple count and whether <TT CLASS="COMMAND" >CLUSTER</TT > is using an index to rebuild. </P ></LI ><LI ><P > Prevent <A HREF="routine-vacuuming.html#AUTOVACUUM" >autovacuum</A > from waiting if it cannot acquire a table lock (Robert Haas) </P ><P > It will try to vacuum that table later. </P ></LI ></UL ></DIV ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119724" >E.50.3.5.4. <A HREF="sql-cluster.html" ><TT CLASS="COMMAND" >CLUSTER</TT ></A ></A ></H4 ><P ></P ><UL ><LI ><P > Allow <TT CLASS="COMMAND" >CLUSTER</TT > to sort the table rather than scanning the index when it seems likely to be cheaper (Leonardo Francalanci) </P ></LI ></UL ></DIV ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119732" >E.50.3.5.5. Indexes</A ></H4 ><P ></P ><UL ><LI ><P > Add nearest-neighbor (order-by-operator) searching to <A HREF="gist.html" ><ACRONYM CLASS="ACRONYM" >GiST</ACRONYM > indexes</A > (Teodor Sigaev, Tom Lane) </P ><P > This allows <ACRONYM CLASS="ACRONYM" >GiST</ACRONYM > indexes to quickly return the <TT CLASS="REPLACEABLE" ><I >N</I ></TT > closest values in a query with <TT CLASS="LITERAL" >LIMIT</TT >. For example </P><PRE CLASS="PROGRAMLISTING" >SELECT * FROM places ORDER BY location <-> point '(101,456)' LIMIT 10;</PRE ><P> finds the ten places closest to a given target point. </P ></LI ><LI ><P > Allow <A HREF="gin.html" ><ACRONYM CLASS="ACRONYM" >GIN</ACRONYM > indexes</A > to index null and empty values (Tom Lane) </P ><P > This allows full <ACRONYM CLASS="ACRONYM" >GIN</ACRONYM > index scans, and fixes various corner cases in which GIN scans would fail. </P ></LI ><LI ><P > Allow <A HREF="gin.html" ><ACRONYM CLASS="ACRONYM" >GIN</ACRONYM > indexes</A > to better recognize duplicate search entries (Tom Lane) </P ><P > This reduces the cost of index scans, especially in cases where it avoids unnecessary full index scans. </P ></LI ><LI ><P > Fix <A HREF="gist.html" ><ACRONYM CLASS="ACRONYM" >GiST</ACRONYM > indexes</A > to be fully crash-safe (Heikki Linnakangas) </P ><P > Previously there were rare cases where a <TT CLASS="COMMAND" >REINDEX</TT > would be required (you would be informed). </P ></LI ></UL ></DIV ></DIV ><DIV CLASS="SECT3" ><H3 CLASS="SECT3" ><A NAME="AEN119761" >E.50.3.6. Data Types</A ></H3 ><P ></P ><UL ><LI ><P > Allow <TT CLASS="TYPE" >numeric</TT > to use a more compact, two-byte header in common cases (Robert Haas) </P ><P > Previously all <TT CLASS="TYPE" >numeric</TT > values had four-byte headers; this change saves on disk storage. </P ></LI ><LI ><P > Add support for dividing <TT CLASS="TYPE" >money</TT > by <TT CLASS="TYPE" >money</TT > (Andy Balholm) </P ></LI ><LI ><P > Allow binary I/O on type <TT CLASS="TYPE" >void</TT > (Radoslaw Smogura) </P ></LI ><LI ><P > Improve hypotenuse calculations for geometric operators (Paul Matthews) </P ><P > This avoids unnecessary overflows, and may also be more accurate. </P ></LI ><LI ><P > Support hashing array values (Tom Lane) </P ><P > This provides additional query optimization possibilities. </P ></LI ><LI ><P > Don't treat a composite type as sortable unless all its column types are sortable (Tom Lane) </P ><P > This avoids possible <SPAN CLASS="QUOTE" >"could not identify a comparison function"</SPAN > failures at runtime, if it is possible to implement the query without sorting. Also, <TT CLASS="COMMAND" >ANALYZE</TT > won't try to use inappropriate statistics-gathering methods for columns of such composite types. </P ></LI ></UL ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119787" >E.50.3.6.1. Casting</A ></H4 ><P ></P ><UL ><LI ><P > Add support for casting between <TT CLASS="TYPE" >money</TT > and <TT CLASS="TYPE" >numeric</TT > (Andy Balholm) </P ></LI ><LI ><P > Add support for casting from <TT CLASS="TYPE" >int4</TT > and <TT CLASS="TYPE" >int8</TT > to <TT CLASS="TYPE" >money</TT > (Joey Adams) </P ></LI ><LI ><P > Allow casting a table's row type to the table's supertype if it's a typed table (Peter Eisentraut) </P ><P > This is analogous to the existing facility that allows casting a row type to a supertable's row type. </P ></LI ></UL ></DIV ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119802" >E.50.3.6.2. <A HREF="functions-xml.html" ><ACRONYM CLASS="ACRONYM" >XML</ACRONYM ></A ></A ></H4 ><P ></P ><UL ><LI ><P > Add <ACRONYM CLASS="ACRONYM" >XML</ACRONYM > function <A HREF="functions-xml.html#XML-EXISTS" ><TT CLASS="LITERAL" >XMLEXISTS</TT ></A > and <A HREF="functions-xml.html#XML-EXISTS" ><CODE CLASS="FUNCTION" >xpath_exists()</CODE ></A > functions (Mike Fowler) </P ><P > These are used for XPath matching. </P ></LI ><LI ><P > Add <ACRONYM CLASS="ACRONYM" >XML</ACRONYM > functions <A HREF="functions-xml.html#XML-IS-WELL-FORMED" ><CODE CLASS="FUNCTION" >xml_is_well_formed()</CODE ></A >, <A HREF="functions-xml.html#XML-IS-WELL-FORMED" ><CODE CLASS="FUNCTION" >xml_is_well_formed_document()</CODE ></A >, <A HREF="functions-xml.html#XML-IS-WELL-FORMED" ><CODE CLASS="FUNCTION" >xml_is_well_formed_content()</CODE ></A > (Mike Fowler) </P ><P > These check whether the input is properly-formed <ACRONYM CLASS="ACRONYM" >XML</ACRONYM >. They provide functionality that was previously available only in the deprecated <TT CLASS="FILENAME" >contrib/xml2</TT > module. </P ></LI ></UL ></DIV ></DIV ><DIV CLASS="SECT3" ><H3 CLASS="SECT3" ><A NAME="AEN119827" >E.50.3.7. Functions</A ></H3 ><P ></P ><UL ><LI ><P > Add SQL function <A HREF="functions-string.html#FORMAT" ><CODE CLASS="FUNCTION" >format(text, ...)</CODE ></A >, which behaves analogously to C's <CODE CLASS="FUNCTION" >printf()</CODE > (Pavel Stehule, Robert Haas) </P ><P > It currently supports formats for strings, SQL literals, and SQL identifiers. </P ></LI ><LI ><P > Add string functions <A HREF="functions-string.html#FUNCTIONS-STRING-OTHER" ><CODE CLASS="FUNCTION" >concat()</CODE ></A >, <A HREF="functions-string.html#FUNCTIONS-STRING-OTHER" ><CODE CLASS="FUNCTION" >concat_ws()</CODE ></A >, <A HREF="functions-string.html#FUNCTIONS-STRING-OTHER" ><CODE CLASS="FUNCTION" >left()</CODE ></A >, <A HREF="functions-string.html#FUNCTIONS-STRING-OTHER" ><CODE CLASS="FUNCTION" >right()</CODE ></A >, and <A HREF="functions-string.html#FUNCTIONS-STRING-OTHER" ><CODE CLASS="FUNCTION" >reverse()</CODE ></A > (Pavel Stehule) </P ><P > These improve compatibility with other database products. </P ></LI ><LI ><P > Add function <A HREF="functions-admin.html#FUNCTIONS-ADMIN-GENFILE" ><CODE CLASS="FUNCTION" >pg_read_binary_file()</CODE ></A > to read binary files (Dimitri Fontaine, Itagaki Takahiro) </P ></LI ><LI ><P > Add a single-parameter version of function <A HREF="functions-admin.html#FUNCTIONS-ADMIN-GENFILE" ><CODE CLASS="FUNCTION" >pg_read_file()</CODE ></A > to read an entire file (Dimitri Fontaine, Itagaki Takahiro) </P ></LI ><LI ><P > Add three-parameter forms of <A HREF="functions-array.html#ARRAY-FUNCTIONS-TABLE" ><CODE CLASS="FUNCTION" >array_to_string()</CODE ></A > and <A HREF="functions-array.html#ARRAY-FUNCTIONS-TABLE" ><CODE CLASS="FUNCTION" >string_to_array()</CODE ></A > for null value processing control (Pavel Stehule) </P ></LI ></UL ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119863" >E.50.3.7.1. Object Information Functions</A ></H4 ><P ></P ><UL ><LI ><P > Add the <A HREF="functions-info.html#FUNCTIONS-INFO-CATALOG-TABLE" ><CODE CLASS="FUNCTION" >pg_describe_object()</CODE ></A > function (Alvaro Herrera) </P ><P > This function is used to obtain a human-readable string describing an object, based on the <A HREF="catalog-pg-class.html" ><TT CLASS="STRUCTNAME" >pg_class</TT ></A > OID, object OID, and sub-object ID. It can be used to help interpret the contents of <A HREF="catalog-pg-depend.html" ><TT CLASS="STRUCTNAME" >pg_depend</TT ></A >. </P ></LI ><LI ><P > Update comments for built-in operators and their underlying functions (Tom Lane) </P ><P > Functions that are meant to be used via an associated operator are now commented as such. </P ></LI ><LI ><P > Add variable <A HREF="runtime-config-compatible.html#GUC-QUOTE-ALL-IDENTIFIERS" ><TT CLASS="VARNAME" >quote_all_identifiers</TT ></A > to force the quoting of all identifiers in <TT CLASS="COMMAND" >EXPLAIN</TT > and in system catalog functions like <A HREF="functions-info.html#FUNCTIONS-INFO-CATALOG-TABLE" ><CODE CLASS="FUNCTION" >pg_get_viewdef()</CODE ></A > (Robert Haas) </P ><P > This makes exporting schemas to tools and other databases with different quoting rules easier. </P ></LI ><LI ><P > Add columns to the <A HREF="infoschema-sequences.html" ><TT CLASS="STRUCTNAME" >information_schema.sequences</TT ></A > system view (Peter Eisentraut) </P ><P > Previously, though the view existed, the columns about the sequence parameters were unimplemented. </P ></LI ><LI ><P > Allow <TT CLASS="LITERAL" >public</TT > as a pseudo-role name in <A HREF="functions-info.html#FUNCTIONS-INFO-ACCESS-TABLE" ><CODE CLASS="FUNCTION" >has_table_privilege()</CODE ></A > and related functions (Alvaro Herrera) </P ><P > This allows checking for public permissions. </P ></LI ></UL ></DIV ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119897" >E.50.3.7.2. Function and Trigger Creation</A ></H4 ><P ></P ><UL ><LI ><P > Support <A HREF="sql-createtrigger.html" ><TT CLASS="LITERAL" >INSTEAD OF</TT ></A > triggers on views (Dean Rasheed) </P ><P > This feature can be used to implement fully updatable views. </P ></LI ></UL ></DIV ></DIV ><DIV CLASS="SECT3" ><H3 CLASS="SECT3" ><A NAME="AEN119905" >E.50.3.8. Server-Side Languages</A ></H3 ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119907" >E.50.3.8.1. <A HREF="plpgsql.html" >PL/pgSQL</A > Server-Side Language</A ></H4 ><P ></P ><UL ><LI ><P > Add <A HREF="plpgsql-control-structures.html#PLPGSQL-FOREACH-ARRAY" ><TT CLASS="COMMAND" >FOREACH IN ARRAY</TT ></A > to PL/pgSQL (Pavel Stehule) </P ><P > This is more efficient and readable than previous methods of iterating through the elements of an array value. </P ></LI ><LI ><P > Allow <TT CLASS="COMMAND" >RAISE</TT > without parameters to be caught in the same places that could catch a <TT CLASS="COMMAND" >RAISE ERROR</TT > from the same location (Piyush Newe) </P ><P > The previous coding threw the error from the block containing the active exception handler. The new behavior is more consistent with other DBMS products. </P ></LI ></UL ></DIV ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119921" >E.50.3.8.2. <A HREF="plperl.html" >PL/Perl</A > Server-Side Language</A ></H4 ><P ></P ><UL ><LI ><P > Allow generic record arguments to PL/Perl functions (Andrew Dunstan) </P ><P > PL/Perl functions can now be declared to accept type <TT CLASS="TYPE" >record</TT >. The behavior is the same as for any named composite type. </P ></LI ><LI ><P > Convert PL/Perl array arguments to Perl arrays (Alexey Klyukin, Alex Hunsaker) </P ><P > String representations are still available. </P ></LI ><LI ><P > Convert PL/Perl composite-type arguments to Perl hashes (Alexey Klyukin, Alex Hunsaker) </P ><P > String representations are still available. </P ></LI ></UL ></DIV ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119935" >E.50.3.8.3. <A HREF="plpython.html" >PL/Python</A > Server-Side Language</A ></H4 ><P ></P ><UL ><LI ><P > Add table function support for PL/Python (Jan Urbanski) </P ><P > PL/Python can now return multiple <TT CLASS="LITERAL" >OUT</TT > parameters and record sets. </P ></LI ><LI ><P > Add a validator to PL/Python (Jan Urbanski) </P ><P > This allows PL/Python functions to be syntax-checked at function creation time. </P ></LI ><LI ><P > Allow exceptions for SQL queries in PL/Python (Jan Urbanski) </P ><P > This allows access to SQL-generated exception error codes from PL/Python exception blocks. </P ></LI ><LI ><P > Add explicit subtransactions to PL/Python (Jan Urbanski) </P ></LI ><LI ><P > Add PL/Python functions for quoting strings (Jan Urbanski) </P ><P > These functions are <A HREF="plpython-util.html" ><TT CLASS="LITERAL" >plpy.quote_ident</TT ></A >, <A HREF="plpython-util.html" ><TT CLASS="LITERAL" >plpy.quote_literal</TT ></A >, and <A HREF="plpython-util.html" ><TT CLASS="LITERAL" >plpy.quote_nullable</TT ></A >. </P ></LI ><LI ><P > Add traceback information to PL/Python errors (Jan Urbanski) </P ></LI ><LI ><P > Report PL/Python errors from iterators with <TT CLASS="LITERAL" >PLy_elog</TT > (Jan Urbanski) </P ></LI ><LI ><P > Fix exception handling with Python 3 (Jan Urbanski) </P ><P > Exception classes were previously not available in <TT CLASS="LITERAL" >plpy</TT > under Python 3. </P ></LI ></UL ></DIV ></DIV ><DIV CLASS="SECT3" ><H3 CLASS="SECT3" ><A NAME="AEN119969" >E.50.3.9. Client Applications</A ></H3 ><P ></P ><UL ><LI ><P > Mark <A HREF="app-createlang.html" ><SPAN CLASS="APPLICATION" >createlang</SPAN ></A > and <A HREF="app-droplang.html" ><SPAN CLASS="APPLICATION" >droplang</SPAN ></A > as deprecated now that they just invoke extension commands (Tom Lane) </P ></LI ></UL ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN119978" >E.50.3.9.1. <A HREF="app-psql.html" ><SPAN CLASS="APPLICATION" >psql</SPAN ></A ></A ></H4 ><P ></P ><UL ><LI ><P > Add <SPAN CLASS="APPLICATION" >psql</SPAN > command <TT CLASS="LITERAL" >\conninfo</TT > to show current connection information (David Christensen) </P ></LI ><LI ><P > Add <SPAN CLASS="APPLICATION" >psql</SPAN > command <TT CLASS="LITERAL" >\sf</TT > to show a function's definition (Pavel Stehule) </P ></LI ><LI ><P > Add <SPAN CLASS="APPLICATION" >psql</SPAN > command <TT CLASS="LITERAL" >\dL</TT > to list languages (Fernando Ike) </P ></LI ><LI ><P > Add the <TT CLASS="OPTION" >S</TT > (<SPAN CLASS="QUOTE" >"system"</SPAN >) option to <SPAN CLASS="APPLICATION" >psql</SPAN >'s <TT CLASS="LITERAL" >\dn</TT > (list schemas) command (Tom Lane) </P ><P > <TT CLASS="LITERAL" >\dn</TT > without <TT CLASS="LITERAL" >S</TT > now suppresses system schemas. </P ></LI ><LI ><P > Allow <SPAN CLASS="APPLICATION" >psql</SPAN >'s <TT CLASS="LITERAL" >\e</TT > and <TT CLASS="LITERAL" >\ef</TT > commands to accept a line number to be used to position the cursor in the editor (Pavel Stehule) </P ><P > This is passed to the editor according to the <TT CLASS="ENVAR" >PSQL_EDITOR_LINENUMBER_ARG</TT > environment variable. </P ></LI ><LI ><P > Have <SPAN CLASS="APPLICATION" >psql</SPAN > set the client encoding from the operating system locale by default (Heikki Linnakangas) </P ><P > This only happens if the <TT CLASS="ENVAR" >PGCLIENTENCODING</TT > environment variable is not set. </P ></LI ><LI ><P > Make <TT CLASS="LITERAL" >\d</TT > distinguish between unique indexes and unique constraints (Josh Kupershmidt) </P ></LI ><LI ><P > Make <TT CLASS="LITERAL" >\dt+</TT > report <CODE CLASS="FUNCTION" >pg_table_size</CODE > instead of <CODE CLASS="FUNCTION" >pg_relation_size</CODE > when talking to 9.0 or later servers (Bernd Helmle) </P ><P > This is a more useful measure of table size, but note that it is not identical to what was previously reported in the same display. </P ></LI ><LI ><P > Additional tab completion support (Itagaki Takahiro, Pavel Stehule, Andrey Popp, Christoph Berg, David Fetter, Josh Kupershmidt) </P ></LI ></UL ></DIV ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN120027" >E.50.3.9.2. <A HREF="app-pgdump.html" ><SPAN CLASS="APPLICATION" >pg_dump</SPAN ></A ></A ></H4 ><P ></P ><UL ><LI ><P > Add <A HREF="app-pgdump.html" ><SPAN CLASS="APPLICATION" >pg_dump</SPAN ></A > and <A HREF="app-pg-dumpall.html" ><SPAN CLASS="APPLICATION" >pg_dumpall</SPAN ></A > option <TT CLASS="OPTION" >--quote-all-identifiers</TT > to force quoting of all identifiers (Robert Haas) </P ></LI ><LI ><P > Add <TT CLASS="LITERAL" >directory</TT > format to <SPAN CLASS="APPLICATION" >pg_dump</SPAN > (Joachim Wieland, Heikki Linnakangas) </P ><P > This is internally similar to the <TT CLASS="LITERAL" >tar</TT > <SPAN CLASS="APPLICATION" >pg_dump</SPAN > format. </P ></LI ></UL ></DIV ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN120046" >E.50.3.9.3. <A HREF="app-pg-ctl.html" ><SPAN CLASS="APPLICATION" >pg_ctl</SPAN ></A ></A ></H4 ><P ></P ><UL ><LI ><P > Fix <SPAN CLASS="APPLICATION" >pg_ctl</SPAN > so it no longer incorrectly reports that the server is not running (Bruce Momjian) </P ><P > Previously this could happen if the server was running but <SPAN CLASS="APPLICATION" >pg_ctl</SPAN > could not authenticate. </P ></LI ><LI ><P > Improve <SPAN CLASS="APPLICATION" >pg_ctl</SPAN > start's <SPAN CLASS="QUOTE" >"wait"</SPAN > (<TT CLASS="OPTION" >-w</TT >) option (Bruce Momjian, Tom Lane) </P ><P > The wait mode is now significantly more robust. It will not get confused by non-default postmaster port numbers, non-default Unix-domain socket locations, permission problems, or stale postmaster lock files. </P ></LI ><LI ><P > Add <TT CLASS="LITERAL" >promote</TT > option to <SPAN CLASS="APPLICATION" >pg_ctl</SPAN > to switch a standby server to primary (Fujii Masao) </P ></LI ></UL ></DIV ></DIV ><DIV CLASS="SECT3" ><H3 CLASS="SECT3" ><A NAME="AEN120066" >E.50.3.10. <SPAN CLASS="APPLICATION" >Development Tools</SPAN ></A ></H3 ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN120069" >E.50.3.10.1. <A HREF="libpq.html" ><SPAN CLASS="APPLICATION" >libpq</SPAN ></A ></A ></H4 ><P ></P ><UL ><LI ><P > Add a libpq connection option <A HREF="libpq-connect.html#LIBPQ-CONNECT-CLIENT-ENCODING" ><TT CLASS="LITERAL" >client_encoding</TT ></A > which behaves like the <TT CLASS="ENVAR" >PGCLIENTENCODING</TT > environment variable (Heikki Linnakangas) </P ><P > The value <TT CLASS="LITERAL" >auto</TT > sets the client encoding based on the operating system locale. </P ></LI ><LI ><P > Add <A HREF="libpq-misc.html#LIBPQ-PQLIBVERSION" ><CODE CLASS="FUNCTION" >PQlibVersion()</CODE ></A > function which returns the libpq library version (Magnus Hagander) </P ><P > libpq already had <CODE CLASS="FUNCTION" >PQserverVersion()</CODE > which returns the server version. </P ></LI ><LI ><P > Allow libpq-using clients to check the user name of the server process when connecting via Unix-domain sockets, with the new <A HREF="libpq-connect.html#LIBPQ-CONNECT-REQUIREPEER" ><TT CLASS="LITERAL" >requirepeer</TT ></A > connection option (Peter Eisentraut) </P ><P > <SPAN CLASS="PRODUCTNAME" >PostgreSQL</SPAN > already allowed servers to check the client user name when connecting via Unix-domain sockets. </P ></LI ><LI ><P > Add <A HREF="libpq-connect.html#LIBPQ-PQPING" ><CODE CLASS="FUNCTION" >PQping()</CODE ></A > and <A HREF="libpq-connect.html#LIBPQ-PQPINGPARAMS" ><CODE CLASS="FUNCTION" >PQpingParams()</CODE ></A > to libpq (Bruce Momjian, Tom Lane) </P ><P > These functions allow detection of the server's status without trying to open a new session. </P ></LI ></UL ></DIV ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN120100" >E.50.3.10.2. <A HREF="ecpg.html" ><SPAN CLASS="APPLICATION" >ECPG</SPAN ></A ></A ></H4 ><P ></P ><UL ><LI ><P > Allow ECPG to accept dynamic cursor names even in <TT CLASS="LITERAL" >WHERE CURRENT OF</TT > clauses (Zoltan Boszormenyi) </P ></LI ><LI ><P > Make <SPAN CLASS="APPLICATION" >ecpglib</SPAN > write <TT CLASS="TYPE" >double</TT > values with a precision of 15 digits, not 14 as formerly (Akira Kurosawa) </P ></LI ></UL ></DIV ></DIV ><DIV CLASS="SECT3" ><H3 CLASS="SECT3" ><A NAME="AEN120112" >E.50.3.11. Build Options</A ></H3 ><P ></P ><UL ><LI ><P > Use <TT CLASS="LITERAL" >+Olibmerrno</TT > compile flag with HP-UX C compilers that accept it (Ibrar Ahmed) </P ><P > This avoids possible misbehavior of math library calls on recent HP platforms. </P ></LI ></UL ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN120119" >E.50.3.11.1. Makefiles</A ></H4 ><P ></P ><UL ><LI ><P > Improved parallel make support (Peter Eisentraut) </P ><P > This allows for faster compiles. Also, <TT CLASS="LITERAL" >make -k</TT > now works more consistently. </P ></LI ><LI ><P > Require <ACRONYM CLASS="ACRONYM" >GNU</ACRONYM > <A HREF="install-requirements.html" ><SPAN CLASS="APPLICATION" >make</SPAN ></A > 3.80 or newer (Peter Eisentraut) </P ><P > This is necessary because of the parallel-make improvements. </P ></LI ><LI ><P > Add <TT CLASS="LITERAL" >make maintainer-check</TT > target (Peter Eisentraut) </P ><P > This target performs various source code checks that are not appropriate for either the build or the regression tests. Currently: duplicate_oids, SGML syntax and tabs check, NLS syntax check. </P ></LI ><LI ><P > Support <TT CLASS="LITERAL" >make check</TT > in <TT CLASS="FILENAME" >contrib</TT > (Peter Eisentraut) </P ><P > Formerly only <TT CLASS="LITERAL" >make installcheck</TT > worked, but now there is support for testing in a temporary installation. The top-level <TT CLASS="LITERAL" >make check-world</TT > target now includes testing <TT CLASS="FILENAME" >contrib</TT > this way. </P ></LI ></UL ></DIV ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN120144" >E.50.3.11.2. Windows</A ></H4 ><P ></P ><UL ><LI ><P > On Windows, allow <A HREF="app-pg-ctl.html" ><SPAN CLASS="APPLICATION" >pg_ctl</SPAN ></A > to register the service as auto-start or start-on-demand (Quan Zongliang) </P ></LI ><LI ><P > Add support for collecting <A HREF="installation-platform-notes.html#WINDOWS-CRASH-DUMPS" >crash dumps</A > on Windows (Craig Ringer, Magnus Hagander) </P ><P > <SPAN CLASS="PRODUCTNAME" >minidumps</SPAN > can now be generated by non-debug Windows binaries and analyzed by standard debugging tools. </P ></LI ><LI ><P > Enable building with the MinGW64 compiler (Andrew Dunstan) </P ><P > This allows building 64-bit Windows binaries even on non-Windows platforms via cross-compiling. </P ></LI ></UL ></DIV ></DIV ><DIV CLASS="SECT3" ><H3 CLASS="SECT3" ><A NAME="AEN120159" >E.50.3.12. Source Code</A ></H3 ><P ></P ><UL ><LI ><P > Revise the API for GUC variable assign hooks (Tom Lane) </P ><P > The previous functions of assign hooks are now split between check hooks and assign hooks, where the former can fail but the latter shouldn't. This change will impact add-on modules that define custom GUC parameters. </P ></LI ><LI ><P > Add latches to the source code to support waiting for events (Heikki Linnakangas) </P ></LI ><LI ><P > Centralize data modification permissions-checking logic (KaiGai Kohei) </P ></LI ><LI ><P > Add missing <CODE CLASS="FUNCTION" >get_<TT CLASS="REPLACEABLE" ><I >object</I ></TT >_oid()</CODE > functions, for consistency (Robert Haas) </P ></LI ><LI ><P > Improve ability to use C++ compilers for <A HREF="xfunc-c.html" >compiling add-on modules</A > by removing conflicting key words (Tom Lane) </P ></LI ><LI ><P > Add support for DragonFly <ACRONYM CLASS="ACRONYM" >BSD</ACRONYM > (Rumko) </P ></LI ><LI ><P > Expose <CODE CLASS="FUNCTION" >quote_literal_cstr()</CODE > for backend use (Robert Haas) </P ></LI ><LI ><P > Run <A HREF="install-procedure.html#BUILD" >regression tests</A > in the default encoding (Peter Eisentraut) </P ><P > Regression tests were previously always run with <TT CLASS="LITERAL" >SQL_ASCII</TT > encoding. </P ></LI ><LI ><P > Add <SPAN CLASS="APPLICATION" >src/tools/git_changelog</SPAN > to replace <SPAN CLASS="APPLICATION" >cvs2cl</SPAN > and <SPAN CLASS="APPLICATION" >pgcvslog</SPAN > (Robert Haas, Tom Lane) </P ></LI ><LI ><P > Add <SPAN CLASS="APPLICATION" >git-external-diff</SPAN > script to <TT CLASS="FILENAME" >src/tools</TT > (Bruce Momjian) </P ><P > This is used to generate context diffs from git. </P ></LI ><LI ><P > Improve support for building with <SPAN CLASS="APPLICATION" >Clang</SPAN > (Peter Eisentraut) </P ></LI ></UL ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN120200" >E.50.3.12.1. Server Hooks</A ></H4 ><P ></P ><UL ><LI ><P > Add source code hooks to check permissions (Robert Haas, Stephen Frost) </P ></LI ><LI ><P > Add post-object-creation function hooks for use by security frameworks (KaiGai Kohei) </P ></LI ><LI ><P > Add a client authentication hook (KaiGai Kohei) </P ></LI ></UL ></DIV ></DIV ><DIV CLASS="SECT3" ><H3 CLASS="SECT3" ><A NAME="AEN120209" >E.50.3.13. Contrib</A ></H3 ><P ></P ><UL ><LI ><P > Modify <TT CLASS="FILENAME" >contrib</TT > modules and procedural languages to install via the new <A HREF="extend-extensions.html" >extension</A > mechanism (Tom Lane, Dimitri Fontaine) </P ></LI ><LI ><P > Add <A HREF="file-fdw.html" ><TT CLASS="FILENAME" >contrib/file_fdw</TT ></A > foreign-data wrapper (Shigeru Hanada) </P ><P > Foreign tables using this foreign data wrapper can read flat files in a manner very similar to <TT CLASS="COMMAND" >COPY</TT >. </P ></LI ><LI ><P > Add nearest-neighbor search support to <A HREF="pgtrgm.html" ><TT CLASS="FILENAME" >contrib/pg_trgm</TT ></A > and <A HREF="btree-gist.html" ><TT CLASS="FILENAME" >contrib/btree_gist</TT ></A > (Teodor Sigaev) </P ></LI ><LI ><P > Add <A HREF="btree-gist.html" ><TT CLASS="FILENAME" >contrib/btree_gist</TT ></A > support for searching on not-equals (Jeff Davis) </P ></LI ><LI ><P > Fix <A HREF="fuzzystrmatch.html" ><TT CLASS="FILENAME" >contrib/fuzzystrmatch</TT ></A >'s <CODE CLASS="FUNCTION" >levenshtein()</CODE > function to handle multibyte characters (Alexander Korotkov) </P ></LI ><LI ><P > Add <CODE CLASS="FUNCTION" >ssl_cipher()</CODE > and <CODE CLASS="FUNCTION" >ssl_version()</CODE > functions to <A HREF="sslinfo.html" ><TT CLASS="FILENAME" >contrib/sslinfo</TT ></A > (Robert Haas) </P ></LI ><LI ><P > Fix <A HREF="intarray.html" ><TT CLASS="FILENAME" >contrib/intarray</TT ></A > and <A HREF="hstore.html" ><TT CLASS="FILENAME" >contrib/hstore</TT ></A > to give consistent results with indexed empty arrays (Tom Lane) </P ><P > Previously an empty-array query that used an index might return different results from one that used a sequential scan. </P ></LI ><LI ><P > Allow <A HREF="intarray.html" ><TT CLASS="FILENAME" >contrib/intarray</TT ></A > to work properly on multidimensional arrays (Tom Lane) </P ></LI ><LI ><P > In <A HREF="intarray.html" ><TT CLASS="FILENAME" >contrib/intarray</TT ></A >, avoid errors complaining about the presence of nulls in cases where no nulls are actually present (Tom Lane) </P ></LI ><LI ><P > In <A HREF="intarray.html" ><TT CLASS="FILENAME" >contrib/intarray</TT ></A >, fix behavior of containment operators with respect to empty arrays (Tom Lane) </P ><P > Empty arrays are now correctly considered to be contained in any other array. </P ></LI ><LI ><P > Remove <A HREF="xml2.html" ><TT CLASS="FILENAME" >contrib/xml2</TT ></A >'s arbitrary limit on the number of <TT CLASS="REPLACEABLE" ><I >parameter</I ></TT >=<TT CLASS="REPLACEABLE" ><I >value</I ></TT > pairs that can be handled by <CODE CLASS="FUNCTION" >xslt_process()</CODE > (Pavel Stehule) </P ><P > The previous limit was 10. </P ></LI ><LI ><P > In <A HREF="pageinspect.html" ><TT CLASS="FILENAME" >contrib/pageinspect</TT ></A >, fix heap_page_item to return infomasks as 32-bit values (Alvaro Herrera) </P ><P > This avoids returning negative values, which was confusing. The underlying value is a 16-bit unsigned integer. </P ></LI ></UL ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN120276" >E.50.3.13.1. Security</A ></H4 ><P ></P ><UL ><LI ><P > Add <A HREF="sepgsql.html" ><TT CLASS="FILENAME" >contrib/sepgsql</TT ></A > to interface permission checks with <ACRONYM CLASS="ACRONYM" >SELinux</ACRONYM > (KaiGai Kohei) </P ><P > This uses the new <A HREF="sql-security-label.html" ><TT CLASS="COMMAND" >SECURITY LABEL</TT ></A > facility. </P ></LI ><LI ><P > Add contrib module <A HREF="auth-delay.html" ><TT CLASS="FILENAME" >auth_delay</TT ></A > (KaiGai Kohei) </P ><P > This causes the server to pause before returning authentication failure; it is designed to make brute force password attacks more difficult. </P ></LI ><LI ><P > Add <TT CLASS="FILENAME" >dummy_seclabel</TT > contrib module (KaiGai Kohei) </P ><P > This is used for permission regression testing. </P ></LI ></UL ></DIV ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN120296" >E.50.3.13.2. Performance</A ></H4 ><P ></P ><UL ><LI ><P > Add support for <TT CLASS="LITERAL" >LIKE</TT > and <TT CLASS="LITERAL" >ILIKE</TT > index searches to <A HREF="pgtrgm.html" ><TT CLASS="FILENAME" >contrib/pg_trgm</TT ></A > (Alexander Korotkov) </P ></LI ><LI ><P > Add <CODE CLASS="FUNCTION" >levenshtein_less_equal()</CODE > function to <A HREF="fuzzystrmatch.html" ><TT CLASS="FILENAME" >contrib/fuzzystrmatch</TT ></A >, which is optimized for small distances (Alexander Korotkov) </P ></LI ><LI ><P > Improve performance of index lookups on <A HREF="seg.html" ><TT CLASS="FILENAME" >contrib/seg</TT ></A > columns (Alexander Korotkov) </P ></LI ><LI ><P > Improve performance of <A HREF="pgupgrade.html" ><SPAN CLASS="APPLICATION" >pg_upgrade</SPAN ></A > for databases with many relations (Bruce Momjian) </P ></LI ><LI ><P > Add flag to <A HREF="pgbench.html" ><TT CLASS="FILENAME" >contrib/pgbench</TT ></A > to report per-statement latencies (Florian Pflug) </P ></LI ></UL ></DIV ><DIV CLASS="SECT4" ><H4 CLASS="SECT4" ><A NAME="AEN120322" >E.50.3.13.3. Fsync Testing</A ></H4 ><P ></P ><UL ><LI ><P > Move <TT CLASS="FILENAME" >src/tools/test_fsync</TT > to <A HREF="pgtestfsync.html" ><TT CLASS="FILENAME" >contrib/pg_test_fsync</TT ></A > (Bruce Momjian, Tom Lane) </P ></LI ><LI ><P > Add <TT CLASS="LITERAL" >O_DIRECT</TT > support to <A HREF="pgtestfsync.html" ><TT CLASS="FILENAME" >contrib/pg_test_fsync</TT ></A > (Bruce Momjian) </P ><P > This matches the use of <TT CLASS="LITERAL" >O_DIRECT</TT > by <A HREF="runtime-config-wal.html#GUC-WAL-SYNC-METHOD" ><TT CLASS="VARNAME" >wal_sync_method</TT ></A >. </P ></LI ><LI ><P > Add new tests to <A HREF="pgtestfsync.html" ><TT CLASS="FILENAME" >contrib/pg_test_fsync</TT ></A > (Bruce Momjian) </P ></LI ></UL ></DIV ></DIV ><DIV CLASS="SECT3" ><H3 CLASS="SECT3" ><A NAME="AEN120343" >E.50.3.14. Documentation</A ></H3 ><P ></P ><UL ><LI ><P > Extensive <A HREF="ecpg.html" ><SPAN CLASS="APPLICATION" >ECPG</SPAN ></A > documentation improvements (Satoshi Nagayasu) </P ></LI ><LI ><P > Extensive proofreading and documentation improvements (Thom Brown, Josh Kupershmidt, Susanne Ebrecht) </P ></LI ><LI ><P > Add documentation for <A HREF="runtime-config-error-handling.html#GUC-EXIT-ON-ERROR" ><TT CLASS="VARNAME" >exit_on_error</TT ></A > (Robert Haas) </P ><P > This parameter causes sessions to exit on any error. </P ></LI ><LI ><P > Add documentation for <A HREF="functions-info.html#FUNCTIONS-INFO-CATALOG-TABLE" ><CODE CLASS="FUNCTION" >pg_options_to_table()</CODE ></A > (Josh Berkus) </P ><P > This function shows table storage options in a readable form. </P ></LI ><LI ><P > Document that it is possible to access all composite type fields using <A HREF="sql-expressions.html#FIELD-SELECTION" ><TT CLASS="LITERAL" >(compositeval).*</TT ></A > syntax (Peter Eisentraut) </P ></LI ><LI ><P > Document that <A HREF="functions-string.html#FUNCTIONS-STRING-OTHER" ><CODE CLASS="FUNCTION" >translate()</CODE ></A > removes characters in <TT CLASS="LITERAL" >from</TT > that don't have a corresponding <TT CLASS="LITERAL" >to</TT > character (Josh Kupershmidt) </P ></LI ><LI ><P > Merge documentation for <TT CLASS="COMMAND" >CREATE CONSTRAINT TRIGGER</TT > and <A HREF="sql-createtrigger.html" ><TT CLASS="COMMAND" >CREATE TRIGGER</TT ></A > (Alvaro Herrera) </P ></LI ><LI ><P > Centralize <A HREF="ddl-priv.html" >permission</A > and <A HREF="upgrading.html" >upgrade</A > documentation (Bruce Momjian) </P ></LI ><LI ><P > Add <A HREF="kernel-resources.html#SYSVIPC-PARAMETERS" >kernel tuning documentation</A > for Solaris 10 (Josh Berkus) </P ><P > Previously only Solaris 9 kernel tuning was documented. </P ></LI ><LI ><P > Handle non-ASCII characters consistently in <TT CLASS="FILENAME" >HISTORY</TT > file (Peter Eisentraut) </P ><P > While the <TT CLASS="FILENAME" >HISTORY</TT > file is in English, we do have to deal with non-ASCII letters in contributor names. These are now transliterated so that they are reasonably legible without assumptions about character set. </P ></LI ></UL ></DIV ></DIV ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="release-9-1-1.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="release-9-0-23.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >Release 9.1.1</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="release.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >Release 9.0.23</TD ></TR ></TABLE ></DIV ></BODY ></HTML >