-<!-- $PostgreSQL: pgsql/doc/src/sgml/release.sgml,v 1.476 2006/10/20 16:34:48 alvherre Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/release.sgml,v 1.477 2006/10/20 23:02:20 tgl Exp $ -->
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<note>
<title>Release date</title>
<simpara>2006-1?-??</simpara>
- <para>CURRENT AS OF 2006-09-21</>
+ <para>CURRENT AS OF 2006-10-18</>
</note>
<sect2>
<title>Overview</title>
<para>
- This release adds many improvements to commands and database
- facilities that were requested by users, including:
+ This release adds many functionality and performance improvements that
+ were requested by users, including:
<itemizedlist>
<listitem>
<para>
- Improved sort performance with lower memory usage
+ Query language enhancements including <command>INSERT/UPDATE/DELETE
+ RETURNING</command>, multi-row <literal>VALUES</literal> lists, and
+ optional target-table alias in
+ <command>UPDATE</>/<command>DELETE</command>
</para>
</listitem>
<listitem>
<para>
- More efficient locking with better concurrency
+ Index creation without blocking concurrent
+ <command>INSERT</>/<command>UPDATE</>/<command>DELETE</>
+ operations
</para>
</listitem>
<listitem>
<para>
- New <literal>FILLFACTOR</literal> support for tables and indexes
+ Many query optimization improvements, including support for
+ reordering outer joins
</para>
</listitem>
<listitem>
<para>
- Many query optimization improvements, including support for
- reordering outer joins
+ Improved sorting performance with lower memory usage
+ </para>
+ </listitem>
+
+ <listitem>
+ <para>
+ More efficient locking with better concurrency
</para>
</listitem>
<listitem>
<para>
- Warm standby server enhancements
+ Easier administration of warm standby servers
</para>
</listitem>
<listitem>
<para>
- Monitoring, logging, and performance tuning additions
+ New <literal>FILLFACTOR</literal> support for tables and indexes
</para>
</listitem>
<listitem>
<para>
- Query language enhancements including <literal>RETURNING</literal>
- values, multi-<literal>VALUES</literal> support, and
- self-joins for <command>DELETE</command>
+ Monitoring, logging, and performance tuning additions
</para>
</listitem>
<listitem>
<para>
- Allow table inheritance to be added and removed from pre-existing tables
+ Table inheritance relationships can be defined
+ for and removed from pre-existing tables
</para>
</listitem>
<listitem>
<para>
- Index creation without blocking concurrent
- <command>INSERT</>/<command>UPDATE</>/<command>DELETE</>
- operations
+ <command>COPY TO</command> can copy the output of an arbitrary
+ <command>SELECT</command> statement
</para>
</listitem>
<listitem>
<para>
- <command>COPY TO</command> support for <command>SELECT</command> statements
+ Array improvements, including nulls in arrays
</para>
</listitem>
<listitem>
<para>
- Array and aggregate improvements, including SQL:2003
- statistical functions
+ Aggregate-function improvements, including multiple-input
+ aggregates and SQL:2003 statistical functions
</para>
</listitem>
<listitem>
<para>
- Have <link linkend="SQL-SET-CONSTRAINTS"><command>SET
+ Make <link linkend="functions-comparison">row <literal>IS <optional>NOT</> NULL</literal></link>
+ tests follow <acronym>SQL</> standard semantics (Tom)
+ </para>
+
+ <para>
+ The former behavior conformed to the standard for simple cases
+ with <literal>IS NULL</>, but <literal>IS NOT NULL</> would return
+ true if any row field was non-null, whereas the standard says it
+ should return true only when all fields are non-null.
+ </para>
+ </listitem>
+
+ <listitem>
+ <para>
+ Make <link linkend="SQL-SET-CONSTRAINTS"><command>SET
CONSTRAINT</></link> affect only one constraint (Kris Jurka)
</para>
all constraints with a matching name. In this release,
the schema search path is used to modify only the first
matching constraint. A schema specification is also
- supported.
+ supported. This more nearly conforms to the SQL standard.
</para>
</listitem>
<listitem>
<para>
- Remove rule permission for tables, for security reasons
+ Remove <literal>RULE</> permission for tables, for security reasons
(Tom)
</para>
<para>
- In this release, only a table's owner can create or modify
+ As of this release, only a table's owner can create or modify
rules for the table. For backwards compatibility,
<command>GRANT</>/<command>REVOKE RULE</> is still accepted,
but it does nothing.
<para>
In prior releases, <varname>log_duration</> only printed if
- the query appeared earlier in the logs.
+ the query appeared earlier in the log.
</para>
</listitem>
<listitem>
<para>
- Have <link
+ Make <link
linkend="functions-formatting"><function>to_char(time)</></link>
and <link
linkend="functions-formatting"><function>to_char(interval)</></link>
- treat <literal>'HH'</> and <literal>'HH12'</> as 12-hour
- intervals.
+ treat <literal>HH</> and <literal>HH12</> as 12-hour
+ intervals
</para>
<para>
- Most applications should use <literal>'HH24'</> unless they
+ Most applications should use <literal>HH24</> unless they
want a 12-hour display.
</para>
</listitem>
linkend="datatype-inet"><type>INET</></link> to <link
linkend="datatype-inet"><type>CIDR</></link> (Tom)
</para>
+
+ <para>
+ This ensures that the converted value is actually valid for
+ <type>CIDR</>.
+ </para>
</listitem>
<listitem>
</para>
<para>
- No longer needed now that timezone abbreviations are
- configurable.
+ This variable has been superseded by a more general facility
+ for configuring timezone abbreviations.
</para>
</listitem>
<listitem>
<para>
-
Change <link linkend="libpq"><application>libpq</></link>
- <function>PQgetssl()</> to return a <literal>void *</>,
+
Declare <link linkend="libpq"><application>libpq</></link>
+ <function>PQgetssl()</> as returning <literal>void *</>,
rather than <literal>SSL *</> (Martijn van Oosterhout)
</para>
<para>
<function>xml_valid()</> will remain for backward compatibility,
- but its behavior will change to do schema checks in future
- releases.
+ but its behavior will change to do schema checking in a future
+ release.
</para>
</listitem>
<listitem>
<para>
- Remove abandoned contrib modules: mSQL-interface, ips
+ Remove abandoned contrib modules: mSQL-interface, tips
</para>
</listitem>
<title>Changes</title>
<para>
- Below you will find a detailed account of the additional
+ Below you will find a detailed account of the
changes between <productname>PostgreSQL</productname> 8.2 and
the previous major release.
</para>
</para>
</listitem>
- <listitem>
- <para>
- Improve <command>COPY</> performance (Alon Goldshuv, Tom)
- </para>
- </listitem>
-
<listitem>
<para>
Add <literal>FILLFACTOR</> to <link
</para>
<para>
- This adds extra free space to each table or index page,
+ This leaves extra free space in each table or index page,
allowing improved performance as the database grows. This
is particularly valuable to maintain <command>CLUSTER</>ing.
</para>
<listitem>
<para>
- Improve locking performance by breaking locks into sections
+ Improve locking performance by breaking the lock manager tables into
+ sections
(Tom)
</para>
<para>
In previous releases, outer joins would always be evaluated in
- the order specified by the query. This change means that the
- query optimizer will consider reordering outer joins in some
- cases, provided that the join order can be changed without
+ the order written in the query. This change allows the
+ query optimizer to consider reordering outer joins, in cases where
+ it can determine that the join order can be changed without
altering the meaning of the query. This can make a
considerable performance difference for queries involving
- multiple outer joins.
+ multiple outer joins or mixed inner and outer joins.
</para>
</listitem>
<listitem>
<para>
- <function>MIN()</> and <function>MAX()</> can now use indexes
- in more cases (Tom)
+ Improve planning of constant <literal>WHERE</> clauses, such as
+ a condition that depends only on variables inherited from an
+ outer query level (Tom)
+ </para>
+ </listitem>
+
+ <listitem>
+ <para>
+ Protocol-level unnamed prepared statements are re-planned
+ for each set of <literal>BIND</> values (Tom)
+ </para>
+
+ <para>
+ This improves performance because the exact parameter values
+ can be used in the plan.
</para>
</listitem>
<listitem>
<para>
- Improve multicolumn <link linkend="GiST"><acronym>GiST</></link>
- indexing (Oleg, Teodor)
+ Avoid extra scan of tables without indexes during <link
+ linkend="SQL-VACUUM"><command>VACUUM</></link> (Greg Stark)
</para>
</listitem>
<listitem>
<para>
- <link linkend="GiST"><acronym>GiST</></link> indexes now
- are clusterable (Teodor)
+ Improve multicolumn <link linkend="GiST"><acronym>GiST</></link>
+ indexing (Oleg, Teodor)
</para>
</listitem>
</para>
<para>
- This is valuable for keeping continuous archiving servers
- in sync with the master. xlog file switching also happens
+ This is valuable for keeping warm standby slave servers
+ in sync with the master. xlog file switching now also happens
automatically during <link
linkend="functions-admin"><function>pg_stop_backup()</></link>.
- This ensures that continuous archiving servers have all
- xlog files needed for recovery.
+ This ensures that all
+ xlog files needed for recovery can be archived immediately.
</para>
</listitem>
point and determining <acronym>WAL</> filenames from the
hex <acronym>WAL</> locations displayed by <link
linkend="functions-admin"><function>pg_stop_backup()</></link>
- and friends.
+ and related functions.
</para>
</listitem>
<listitem>
<para>
- Allow <acronym>WAL</> replay to be restored quicker in case
- of a crash (Simon)
+ Improve recovery from a crash during <acronym>WAL</> replay (Simon)
</para>
<para>
The server now does periodic checkpoints during <acronym>WAL</>
recovery, so if there is a crash, future <acronym>WAL</>
recovery is shortened. This also eliminates the need for
- continuous archive servers to replay the entire log since the
+ warm standby servers to replay the entire log since the
base backup if they crash.
</para>
</listitem>
</para>
<para>
- This enforces a maximum delay for continuous archive servers.
+ This enforces a maximum replication delay for warm standby servers.
</para>
</listitem>
<listitem>
<para>
Add <link linkend="sql-grant-description-objects"><literal>GRANT
- CONNECT ON DATABASE</></link>, to be used in addition to
- <link linkend="auth-pg-hba-conf"><filename>pg_hba.conf</></link>
- (Gevik Babakhani)
+ CONNECT ON DATABASE</></link> (Gevik Babakhani)
</para>
<para>
- This gives SQL-control over database access, and works in
- combination with the existing <filename>pg_hba.conf</>
+ This gives SQL-level control over database access. It works as
+ an additional filter on top of the existing
+ <link linkend="auth-pg-hba-conf"><filename>pg_hba.conf</></link>
controls.
</para>
</listitem>
<listitem>
<para>
Add support for <link linkend="ssl-tcp"><acronym>SSL</>
- Certificate Revocation List</link> (<acronym>CRL</>) files,
- <filename>root.crl</> (Libor Hohoš)
+ Certificate Revocation List</link> (<acronym>CRL</>) files
+ (Libor Hohoš)
</para>
<para>
- This was added to <application>libpq</> as well.
+ The server and <application>libpq</> both recognize <acronym>CRL</>
+ files now.
+ </para>
+ </listitem>
+
+ <listitem>
+ <para>
+ <link linkend="GiST"><acronym>GiST</></link> indexes are
+ now clusterable (Teodor)
</para>
</listitem>
<para>
These values now appear in the <link
linkend="monitoring-stats-views-table"><literal>pg_stat_*_tables</></link>
- system views, and are used by autovacuum. ?
+ system views.
</para>
</listitem>
</para>
<para>
- This allows <literal>pg_stat_activity</> to show the same
- information as the <literal>ps</> display.
+ This allows <structname>pg_stat_activity</> to show all the
+ information included in the <application>ps</> display.
</para>
</listitem>
<listitem>
<para>
- Add <acronym>GUC</> variable <link
+ Add configuration parameter <link
linkend="guc-update-process-title"><varname>update_process_title</></link>
to control whether the <application>ps</> display is updated
- for every command, default to <literal>on</> (Bruce)
+ for every command (Bruce)
+ </para>
+
+ <para>
+ On platforms where it is expensive to update the <application>ps</>
+ display, it may be worthwhile to turn this off and rely solely on
+ <structname>pg_stat_activity</> for status information.
</para>
</listitem>
<para>
For example, you can now set <link
- linkend="guc-shared-buffers"><varname>shared_buffer</></link>
- to <literal>32000kB</>.
+ linkend="guc-shared-buffers"><varname>shared_buffers</></link>
+ to <literal>32MB</> rather than mentally converting sizes.
</para>
</listitem>
</para>
</listitem>
+ <listitem>
+ <para>
+ Prevent <link
+ linkend="guc-max-stack-depth"><varname>max_stack_depth</></link>
+ from being set to unsafe values
+ </para>
+
+ <para>
+ On platforms where we can determine the actual kernel stack depth
+ limit (which is most), make sure that the initial default value of
+ <varname>max_stack_depth</> is safe, and reject attempts to set it
+ to unsafely large values.
+ </para>
+ </listitem>
+
+ <listitem>
+ <para>
+ Enable highlighting of error location in query in more
+ cases (Tom)
+ </para>
+
+ <para>
+ The server is now able to report a specific error location for
+ some semantic errors (such as unrecognized column name), rather
+ than just for basic syntax errors as before.
+ </para>
+ </listitem>
+
</itemizedlist>
</sect3>
<listitem>
<para>
Add support for multiple-row <link
- linkend="queries-values"><literal>VALUES</></link> clauses
- as part of <command>INSERT</> and <command>SELECT</>
- statements, per SQL standard (Joe, Tom)
+ linkend="queries-values"><literal>VALUES</></link> clauses,
+ per SQL standard (Joe, Tom)
</para>
<para>
</para>
<para>
- This allows these statements to support self-joins more
- conveniently. <command>UPDATE</> already supported as
- <literal>FROM</> clause, but <command>DELETE</> did not.
+ The SQL standard does not permit an alias in these commands, but
+ many database systems allow one anyway for notational convenience.
</para>
</listitem>
</para>
<para>
- This is basically as short-hand for assigning the columns
+ This is basically a short-hand for assigning the columns
and values in pairs. The syntax is <literal>UPDATE tab
- SET (col, ...) = (val, ...)</>.
+ SET (<replaceable>column</>, ...) = (<replaceable>val</>, ...)</>.
</para>
</listitem>
<listitem>
<para>
- Allow additional row value comparisons (Tom)
+ Make row comparisons work per standard (Tom)
</para>
<para>
- Add <, <=, >, >=.
+ The forms <, <=, >, >= now compare rows lexicographically,
+ that is, compare the first elements, if equal compare the second
+ elements, and so on. Formerly they expanded to an AND condition
+ across all the elements, which was neither standard nor very useful.
</para>
</listitem>
</para>
<para>
- This allows <command>TRUNCATE</> to automatically truncate all
- foreign-key referencing tables.
+ This causes <command>TRUNCATE</> to automatically include all tables
+ that reference the specified table(s) via foreign keys. While
+ convenient, this is a dangerous tool — use with caution!
</para>
</listitem>
</para>
<para>
- When all columns are of the same defined length, that length
- is used for output, rather than a generic length.
+ When all corresponding columns are of the same defined length, that
+ length is used for the result, rather than a generic length.
</para>
</listitem>
<para>
Internally, <literal>ILIKE</> now calls <function>lower()</>
and then uses <literal>LIKE</>. Locale-specific regular
- expression operations still do not work in these encodings.
+ expression patterns still do not work in these encodings.
</para>
</listitem>
</para>
<para>
- This allow special backslash escaping in strings to be
- turned off so <productname>PostgreSQL</> is more
- standards-compliant. The default is <literal>off</>, but
- future releases will default this to <literal>on</>.
+ This allows backslash escaping in strings to be disabled,
+ making <productname>PostgreSQL</> more
+ standards-compliant. The default is <literal>off</> for backwards
+ compatibility, but future releases will default this to <literal>on</>.
</para>
</listitem>
<listitem>
<para>
- Add system view <link
- linkend="view-pg-prepared-statements"><literal>pg_prepared_statements</></link>
- to show prepared statements (Joachim Wieland, Neil)
+ Do not flatten subqueries that contain <literal>volatile</>
+ functions in their target lists (Jaime Casanova)
+ </para>
+
+ <para>
+ This prevents surprising behavior due to multiple evaluation
+ of a <literal>volatile</> function (such as <function>random()</>
+ or <function>nextval()</>). It may cause performance
+ degradation in the presence of functions that are unnecessarily
+ marked as <literal>volatile</>.
</para>
</listitem>
<listitem>
<para>
- Add system view <link
- linkend="view-pg-cursors"><literal>pg_cursors</></link> to
- show open cursors (Joachim Wieland, Neil)
+ Add system views <link
+ linkend="view-pg-prepared-statements"><literal>pg_prepared_statements</></link>
+ and <link
+ linkend="view-pg-cursors"><literal>pg_cursors</></link>
+ to show prepared statements and open cursors (Joachim Wieland, Neil)
</para>
<para>
- This, and <literal>pg_prepared_statements</> above, are very
- useful for pooled connection setups.
+ These are very useful in pooled connection setups.
</para>
</listitem>
</para>
<para>
- This allows, for example, <literal>?</> parameters to work
- in these commands in <acronym>JDBC</>.
+ This allows, for example, <acronym>JDBC</> <literal>?</> parameters to
+ work in these commands.
</para>
</listitem>
<para>
If <acronym>SQL</>-level <link
linkend="SQL-PREPARE"><command>PREPARE</></link> parameters
- are unspecified, infer their types from the context of the
+ are unspecified, infer their types from the content of the
query (Neil)
</para>
</para>
</listitem>
- <listitem>
- <para>
- Protocol-level unnamed prepared statements are re-planned
- for each set of <literal>BIND</> values (Tom)
- </para>
-
- <para>
- This improves performance because the exact parameter values
- can be used in the plan.
- </para>
- </listitem>
-
<listitem>
<para>
Allow <literal>LIMIT</> and <literal>OFFSET</> to exceed
</para>
<para>
- Shell types create a type reference, without specifying
- any of the aspects of the type. It is useful for creating
- types with input/output functions that reference the data
- type. The syntax is <command>CREATE TYPE <replaceable class="parameter">typename</replaceable></>.
+ A shell type declaration creates a type name, without specifying
+ any of the details of the type. Making a shell type is useful
+ because it allows cleaner declaration of the type's input/output
+ functions, which must exist before the type can be defined <quote>for
+ real</>. The syntax is <command>CREATE TYPE <replaceable
+ class="parameter">typename</replaceable></>.
+ </para>
+ </listitem>
+
+ <listitem>
+ <para>
+ <link linkend="SQL-CREATEAGGREGATE">Aggregate functions</link>
+ now support multiple input parameters (Sergey Koposov, Tom)
</para>
</listitem>
<listitem>
<para>
- <link linkend="SQL-CREATEAGGREGATE">Aggregate functions</link>
- now support multiple input parameters (Sergey Koposov, Tom)
- </para>
- </listitem>
-
- <listitem>
- <para>
- Add <command>CREATE</>/<command>ALTER <link
- linkend="SQL-CREATEROLE">ROLE PASSWORD NULL</link></>,
- which removes the role's password (Peter)
+ Add <link
+ linkend="SQL-ALTERROLE"><command>ALTER ROLE PASSWORD NULL</></link>
+ to remove a previously set role password (Peter)
</para>
</listitem>
</para>
<para>
- <literal>USAGE</> permission allows more find-grained
- control over sequence access. It allows users to increment
+ <literal>USAGE</> permission allows more fine-grained
+ control over sequence access. Granting <literal>USAGE</>
+ allows users to increment
a sequence, but prevents them from setting the sequence to
an arbitrary value using <function>setval()</>.
</para>
<listitem>
<para>
Add <link linkend="SQL-ALTERTABLE"><literal>ALTER TABLE
- ... [ NO ] INHERIT</></link> (Greg Stark)
+ [ NO ] INHERIT</></link> (Greg Stark)
</para>
<para>
- This allow inheritance to be adjusted dynamically, rather than
+ This allows inheritance to be adjusted dynamically, rather than
just at table creation and destruction. This is very valuable
- for table partitioning using constraint exclusion.
+ when using inheritance to implement table partitioning.
</para>
</listitem>
</para>
<para>
- Previously, global object comments were stored in individual
- databases, making them ineffective. This adds a new
- <literal>pg_shdescription</> system catalog.
+ Previously, comments attached to databases were stored in individual
+ databases, making them ineffective, and there was no provision
+ at all for comments on roles. This change adds a new
+ <link
+ linkend="catalog-pg-shdescription"><structname>pg_shdescription</structname></link>
+ system catalog and stores comments on databases and roles therein.
</para>
</listitem>
</para>
<para>
- This is a new locking API that is similar to what used to be
- in /contrib. The /contrib code is now on pgfoundry.
+ This is a new locking API designed to replace what used to be
+ in /contrib/userlock. The userlock code is now on pgfoundry.
</para>
</listitem>
<listitem>
<para>
- Have the <link linkend="SQL-COPY"><command>COPY</></link>
+ Make the <link linkend="SQL-COPY"><command>COPY</></link>
command return a command tag that includes the number of
rows copied (Volkan YAZICI)
</para>
<listitem>
<para>
-
Have <link linkend="APP-INITDB"><application>initdb</></link>
+
Make <link linkend="APP-INITDB"><application>initdb</></link>
detect the operating system locale and set the default
<varname>DateStyle</> accordingly (Peter)
</para>
<para>
This makes it more likely that the installed
<filename>postgresql.conf</> <varname>DateStyle</> value will
- be correct.
- </para>
- </listitem>
-
- <listitem>
- <para>
- Avoid extra scan of tables without indexes during <link
- linkend="SQL-VACUUM"><command>VACUUM</></link> (Greg Stark)
+ be as desired.
</para>
</listitem>
<listitem>
<para>
- Reduce progress messages displayed by <application>initdb</> (Tom)
+ Reduce
number of progress messages displayed by <application>initdb</> (Tom)
</para>
</listitem>
<listitem>
<para>
Allow full timezone names in <link
- linkend="datatype-datetime"><type>timestamp</></link> values
+ linkend="datatype-datetime"><type>timestamp</></link> input values
(Joachim Wieland)
</para>
<listitem>
<para>
- Create a configuration file of timezone abbreviations
- (Joachim Wieland)
+ Support configurable timezone abbreviations (Joachim Wieland)
</para>
<para>
- The file name is controlled by the GUC variable <link
+ A desired set of timezone abbreviations can be chosen via the
+ configuration parameter <link
linkend="guc-timezone-abbreviations"><varname>timezone_abbreviations</></link>.
</para>
</listitem>
<para>
Intervals and times are treated as 24-hour periods, e.g.
- <literal>25 hours</> is <acronym>AM</>.
+ <literal>25 hours</> is
considered <acronym>AM</>.
</para>
</listitem>
</para>
</listitem>
+ <listitem>
+ <para>
+ Allow timezone offsets up to 14:59 away from GMT
+ </para>
+
+ <para>
+ Kiribati uses GMT+14, so we'd better accept that.
+ </para>
+ </listitem>
+
<listitem>
<para>
Interval computation improvements (Michael Glaesemann, Bruce)
<listitem>
<para>
- New <link linkend="functions-array">operators</link>
+ Allow assignment to array elements not contiguous with the existing
+ entries (Tom)
+ </para>
+
+ <para>
+ The intervening array positions will be filled with nulls.
+ This is per SQL standard.
+ </para>
+ </listitem>
+
+ <listitem>
+ <para>
+ New built-in <link linkend="functions-array">operators</link>
for array-subset comparisons (<literal>@></>,
<literal><@</>, <literal>&&</>) (Teodor, Tom)
</para>
<para>
- The old operators were kept for backward compatibility.
+ These operators can be indexed for many data types using
+ <acronym>GiST</> or <acronym>GIN</> indexes.
</para>
</listitem>
<para>
The new operators are <literal>&</> (and), <literal>|</>
- (or), <literal>~</> (not), <literal>+</> <type>int8</>,
- <literal>-</> <type>int8</>, and <type>inet</> <literal>-</>
- <type>inet</>.
+ (or), <literal>~</> (not), <type>inet</> <literal>+</> <type>int8</>,
+ <type>inet</> <literal>-</> <type>int8</>, and
+ <type>inet</> <literal>-</> <type>inet</>.
</para>
</listitem>
<listitem>
<para>
- Add new aggregate <link
- linkend="functions-aggregate-statistics-table">functions</link>
- from SQL2003 (Neil)
+ Add new <link
+ linkend="functions-aggregate-statistics-table">aggregate functions</link>
+ from SQL:2003 (Neil)
</para>
<para>
<function>stddev_samp()</>. <function>var_samp()</> and
<function>stddev_samp()</> are merely renamings of the
existing aggregates <function>variance()</> and
- <function>stddev()</>. The latter names have been kept
+ <function>stddev()</>. The latter names remain available
for backward compatibility.
</para>
</listitem>
<listitem>
<para>
- Add SQL2003-standard statistical <link
+ Add SQL:2003 statistical <link
linkend="functions-aggregate-statistics-table">aggregates</link>
(Sergey Koposov)
</para>
<listitem>
<para>
Allow <link linkend="SQL-CREATEDOMAIN">domains</link> to be
- created using other domains (Tom)
+ based on other domains (Tom)
</para>
</listitem>
<para>
For example, the result of a user-defined function that is
declared to return a domain type is now checked against the
- constraints. This closes a significant hole in the domain
+ domain's constraints. This closes a significant hole in the domain
implementation.
</para>
</listitem>
</para>
</listitem>
- <listitem>
- <para>
- Do not flatten subqueries that contain <literal>VOLATILE</>
- functions in their target lists (Jaime Casanova) ?
- </para>
-
- <para>
- This prevents surprising behavior due to multiple evaluation
- of a <literal>volatile</> function (such as <function>random()</>
- or <function>nextval()</>). It may cause performance
- degradation in the presence of functions that are unnecessarily
- marked as <literal>volatile</>.
- </para>
- </listitem>
-
</itemizedlist>
</sect3>
<listitem>
<para>
- Allow returning of <literal>composite types</> and
- <literal>result sets</> (Sven Suursoho)
+ Allow returning of composite types and result sets (Sven Suursoho)
</para>
</listitem>
</para>
</listitem>
- <listitem>
- <para>
- Return composite-types as dictionary (Sven Suursoho)
- </para>
- </listitem>
-
<listitem>
<para>
Allow functions to return <literal>void</> (Neil)
</para>
<para>
- Use options <literal>-1</> or <literal>--single-transaction</>.
+ Use option <literal>-1</> or <literal>--single-transaction</>.
</para>
</listitem>
</para>
<para>
- This is accomplished using <command>\set FETCH_COUNT</>. This
- feature allows large result sets to be manipulated in
- <application>psql</> without needing to buffer the entire
+ This is enabled using <command>\set FETCH_COUNT
+ <replaceable>n</></command>. This
+ feature allows large result sets to be retrieved in
+ <application>psql</> without attempting to buffer the entire
result set in memory.
</para>
</listitem>
<listitem>
<para>
- Allow multi-line values to align in the proper column
+ Make multi-line values align in the proper column
(Martijn van Oosterhout)
</para>
+
+ <para>
+ Field values containing newlines are now displayed in a more
+ readable fashion.
+ </para>
</listitem>
<listitem>
</para>
<para>
- This makes up-arrow recall of queries easier. (This is
- not available on Win32 because it typically uses the native
- command-line editing present in the operating system.)
- </para>
- </listitem>
-
- <listitem>
- <para>
- Improve highlighting of error location in query in more
- cases (Tom)
+ This makes up-arrow recall of queries easier. (This is
+ not available on Win32, because that platform uses the native
+ command-line editing present in the operating system.)
</para>
</listitem>
<para>
<application>pg_dump</> now supports multiple <literal>-n</>
(schema) and <literal>-t</> (table) options, and adds
- <literal>-T</> and <literal>-N</> options to exclude objects.
- Also adds support for regular expressions for object names
- in these switches.
+ <literal>-N</> and <literal>-T</> options to exclude objects.
+ Also, the arguments of these switches can now be wild-card expressions
+ rather than single object names, for example
+ <literal>-t 'foo*'</>, and a schema can be part of
+ a <literal>-t</> or <literal>-T</> switch, for example
+ <literal>-t schema1.table1</>.
</para>
</listitem>
<para>
Add <link linkend="APP-PGRESTORE"><application>pg_restore</></link>
<literal>--no-data-for-failed-tables</> option to suppress
- loading data if table creation failed (the table already
+ loading data if table creation failed (i.e., the table already
exists) (Martin Pitt)
</para>
</listitem>
</para>
<para>
- Use options <literal>-1</> or <literal>--single-transaction</>.
+ Use option <literal>-1</> or <literal>--single-transaction</>.
</para>
</listitem>
</para>
<para>
- This allows passwords to be sent encrypted for commands
+ This allows passwords to be sent pre-encrypted for commands
like <link linkend="SQL-ALTERROLE"><command>ALTER ROLE ...
PASSWORD</></link>.
</para>
linkend="libpq-exec-main"><function>PQdescribePrepared()</></link>,
<link
linkend="libpq-exec-main"><function>PQdescribePortal()</></link>,
- and related functions return information about previously
+ and related functions to return information about previously
prepared statements and open cursors (Volkan YAZICI)
</para>
</listitem>
<listitem>
<para>
- Allow <acronym>LDAP</> <link linkend="libpq-ldap">lookups</link>
+ Allow <link linkend="libpq-ldap"><acronym>LDAP</></link> lookups
from <link
linkend="libpq-pgservice"><filename>pg_service.conf</></link>
(Laurenz Albe)
<listitem>
<para>
- Allow the <link linkend="libpq-pgpass"><filename>.pgpass</></link>
- hostname to match the default socket directory, as well as
- a blank <literal>pghost</> (Bruce)
+ Allow a hostname in <link
+ linkend="libpq-pgpass"><filename>~/.pgpass</></link>
+ to match the default socket directory (Bruce)
+ </para>
+
+ <para>
+ A blank hostname continues to match any Unix-socket connection,
+ but this addition allows entries that are specific to one of
+ several postmasters on the machine.
</para>
</listitem>
<listitem>
<para>
- Drop privileges on startup so servers can be started from
+ Drop privileges on startup, so that the server can be started from
an administrative account (Magnus)
</para>
</listitem>
<listitem>
<para>
- Improve handling of intermittent file system and resource
- failures (Qingqing Zhou)
- </para>
- </listitem>
-
- <listitem>
- <para>
- Stability fixes (Magnus)
- </para>
-
- <para>
- Particularly, prevent the postmaster from stopping if too
- many connection requests arrive too rapidly.
+ Stability fixes (Qingqing Zhou, Magnus)
</para>
</listitem>
</para>
<para>
- Previous implementations mimicked SysV semaphores.
+ The previous code mimicked SysV semaphores.
</para>
</listitem>
<listitem>
<para>
Add <link linkend="GIN"><acronym>GIN</></link> (Generalized
- Inverted iNdex) index access method (Teodor) ?
+ Inverted iNdex) index access method (Teodor, Oleg)
</para>
</listitem>
<listitem>
<para>
- Reduce libraries linked into the backend needlessly (Martijn
+ Reduce libraries needlessly linked into the backend (Martijn
van Oosterhout, Tom)
</para>
</listitem>
<listitem>
<para>
- Rename existing <acronym>GUC</> variable
+ Add server support for <quote>plugin</> libraries
+ that can be used for add-on tasks such as debugging and performance
+ measurement (Korry Douglas)
+ </para>
+
+ <para>
+ This consists of two features: a table of <quote>rendezvous
+ variables</> that allows separately-loaded shared libraries to
+ communicate, and a new configuration parameter <link
+ linkend="guc-local-preload-libraries"><varname>local_preload_libraries</></link>
+ that allows libraries to be loaded into specific sessions without
+ explicit cooperation from the client application. This allows
+ external add-ons to implement features such as a PL/PgSQL debugger.
+ </para>
+ </listitem>
+
+ <listitem>
+ <para>
+ Rename existing configuration parameter
<varname>preload_libraries</> to <link
linkend="guc-shared-preload-libraries"><varname>shared_preload_libraries</></link>
(Tom)
</para>
+
+ <para>
+ This was done for clarity in comparison to
+ <varname>local_preload_libraries</>.
+ </para>
</listitem>
<listitem>
<para>
- Add new GUC variable <link
+ Add new configuration parameter <link
linkend="guc-server-version-num"><varname>server_version_num</></link>
(Greg Sabino Mullane)
</para>
<listitem>
<para>
- Add a <acronym>GUC</> variable <link
+ Add a configuration parameter <link
linkend="guc-seq-page-cost"><varname>seq_page_cost</></link>
(Tom)
</para>
</para>
<para>
- New <link linkend="xfunc-c-dynload">functions</link>
- <function>_PG_init()</> and <function>_PG_fini()</> are
- called if the library defines such symbols. Hence we no
- longer need to specify an initialization function in
- <varname>shared_preload_libraries</>; we can assume that
- the library used the <function>_PG_init()</> convention
- instead.
+ New <link linkend="xfunc-c-dynload">functions</link>
+ <function>_PG_init()</> and <function>_PG_fini()</> are
+ called if the library defines such symbols. Hence we no
+ longer need to specify an initialization function in
+ <varname>shared_preload_libraries</>; we can assume that
+ the library used the <function>_PG_init()</> convention
+ instead.
</para>
</listitem>
</para>
<para>
- The magic blocks prevent version mismatches between object
+ The magic block prevents version mismatches between loadable object
files and servers.
</para>
</listitem>
- <listitem>
- <para>
- Add support for libraries that enhance server-side languages
- (Korry Douglas)
- </para>
-
- <para>
- Such libraries can be used for debugging or performance
- measurement.
- </para>
- </listitem>
-
<listitem>
<para>
Add shared library support for AIX (Laurenz Albe)
<listitem>
<para>
Ispell dictionaries now recognize <application>MySpell</>
- format, used by <application>OpenOffice</>.
+ format, used by <application>OpenOffice</>
</para>
</listitem>
<listitem>
<listitem>
<para>
- Add <application>Pgadmin</> administration functions to
- adminpack (Dave)
+ Add adminpack module containing <application>Pgadmin</> administration
+ functions (Dave)
</para>
<para>
<listitem>
<para>
- Add sslinfo (Victor Wagner)
+ Add sslinfo module (Victor Wagner)
</para>
<para>
- Reports information about the current <acronym>SSL</>
+ Reports information about the current
connection's <acronym>SSL</>
certificate.
</para>
</listitem>
<listitem>
<para>
- Add pgrowlocks (Tatsuo)
+ Add pgrowlocks module (Tatsuo)
</para>
<para>
</para>
<para>
- This n
ow supports <acronym>EAN13</>, <acronym>UPC</>,
+ This n
ew implementation supports <acronym>EAN13</>, <acronym>UPC</>,
<acronym>ISBN</> (books), <acronym>ISMN</> (music), and
<acronym>ISSN</> (serials).
</para>
<listitem>
<para>
- Add index information to pgstattuple (ITAGAKI Takahiro,
+ Add index information functions to pgstattuple (ITAGAKI Takahiro,
Satoshi Nagayasu)
</para>
</listitem>
<listitem>
<para>
- Add pg_freespacemap to display free space map information
+ Add pg_freespacemap module to display free space map information
(Mark Kirkwood)
</para>
</listitem>
<listitem>
<para>
- Improvements to cube (Joshua Reich)
+ Improvements to cube module (Joshua Reich)
</para>
<para>
New operators for array-subset comparisons (<literal>@></>,
<literal><@</>, <literal>&&</>) (Tom)
</para>
+
+ <para>
+ Various contrib packages already had these operators for their
+ datatypes, but the naming wasn't consistent. We have now added
+ consistently named array-subset comparison operators to the core code
+ and all the contrib packages that have such functionality.
+ (The old names remain available, but are deprecated.)
+ </para>
</listitem>
<listitem>
<para>
- New uninstall scripts for many contrib packages (David)
+ Add uninstall scripts for all contrib packages that have install
+ scripts (David, Josh Drake)
</para>
</listitem>
projects / thirdparty / postgresql.git / commitdiff
