-<!-- $PostgreSQL: pgsql/doc/src/sgml/release-8.5.sgml,v 1.9 2009/12/11 01:33:35 adunstan Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/release-8.5.sgml,v 1.10 2009/12/18 22:11:09 petere Exp $ -->
<sect1 id="release-8-5">
- <title>Release 8.5alpha2</title>
+ <title>Release 8.5alpha3</title>
<sect2>
<title>Overview</title>
<para>
<itemizedlist>
<listitem>
<para>
- <emphasis>Add SQL-compliant triggers on columns, which fire only if
- certain columns are named in the UPDATE's SET list.</>
+ <emphasis>Remove previously deprecated configuration
+ parameter add_missing_from. The system now always behaves as
+ though add_missing_from were off.</emphasis>
</para>
</listitem>
<listitem>
<para>
- <emphasis>Add CREATE LIKE INCLUDING COMMENTS and STORAGE, and INCLUDING
+ <emphasis>Performance and behavioral improvements in UPDATE,
+ DELETE, and SELECT FOR UPDATE/SHARE queries with
+ joins. Various corner-cases could result in duplicated output
+ rows. Set-returning functions are now prohibited in the
+ target list of SELECT FOR UPDATE/SHARE. FOR UPDATE does not
+ propagate into a WITH query anymore.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis>Fixed for SELECT FOR UPDATE/SHARE in conjuction with LIMIT.
+ Previously, it could return fewer rows than the limit specified.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis>Add a WHEN clause to CREATE TRIGGER, allowing a boolean expression
+ to be checked to determine whether the trigger should be fired.</emphasis>
+ </para>
+ <para>
+ <emphasis>For BEFORE triggers this is mostly a matter of spec compliance; but
+ for AFTER triggers it can provide a noticeable performance
+ improvement, since queuing of a deferred trigger event and
+ re-fetching of the row(s) at end of statement can be
+ short-circuited if the trigger does not need to be fired.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis>Add exclusion constraints, which generalize the concept of
+ uniqueness to support any indexable commutative operator, not just
+ equality. Two rows violate the exclusion constraint if
+ "row1.col OP row2.col" is TRUE for each of the columns in
+ the constraint.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis>Support ORDER BY within aggregate function calls, at long last
+ providing a non-kluge method for controlling the order in which
+ values are fed to an aggregate function. At the same time eliminate
+ the old implementation restriction that DISTINCT was only supported
+ for single-argument aggregates.</emphasis>
+ </para>
+ <para>
+ <emphasis>Behavioral change: formerly, agg(DISTINCT x) dropped null values of
+ x unconditionally. Now, it does so only if the agg transition
+ function is strict; otherwise nulls are treated as DISTINCT
+ normally would, i.e., you get one copy.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Add SQL-compliant triggers on columns, which fire only if
+ certain columns are named in the UPDATE's SET list.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Add CREATE LIKE INCLUDING COMMENTS and STORAGE, and INCLUDING
ALL shortcut to allow users to make an exact copy of a table including
- all options and features.</>
+ all options and features.
</para>
</listitem>
<listitem>
<para>
- <emphasis>Define a new, more extensible syntax for COPY options
- in order to support additional COPY options in the future.</>
+ Define a new, more extensible syntax for COPY options
+ in order to support additional COPY options in the future.
</para>
</listitem>
<listitem>
<para>
- <emphasis>Modify the definition of window-function PARTITION
+ Modify the definition of window-function PARTITION
BY and ORDER BY clauses so that their elements are always
taken as simple expressions over the query's input
- columns. This fixes a bug.</>
+ columns. This fixes a bug.
</para>
</listitem>
<listitem>
<para>
- <emphasis>Fix bug with nested WITH RECURSIVE statements.</>
+ Fix bug with nested WITH RECURSIVE statements.
</para>
</listitem>
<listitem>
<para>
- <emphasis>Add surrogate pair support for U& string and identifier
- syntax.</>
+ Add surrogate pair support for U& string and identifier
+ syntax.
</para>
</listitem>
<listitem>
<para>
- <emphasis>Add Unicode escapes in E'...' strings.</>
+ Add Unicode escapes in E'...' strings.
</para>
</listitem>
<listitem>
<itemizedlist>
<listitem>
<para>
- <emphasis>Make TRUNCATE do truncate-in-place when processing
+ <emphasis>Allow rewriting ALTER TABLE to skip WAL logging.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis>Speed up information schema privilege views.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Make TRUNCATE do truncate-in-place when processing
a relation that was created or previously truncated in the
- current (sub)transaction.</>
+ current (sub)transaction.
</para>
</listitem>
<listitem>
<para>
- <emphasis>Implement "join removal" for cases where the inner side
+ Implement "join removal" for cases where the inner side
of a left join is unique and is not referenced above the join. This should
- speed up many ORM-generated and reporting tool queries.</emphasis>
+ speed up many ORM-generated and reporting tool queries.
</para>
</listitem>
<listitem>
<para>
- <emphasis>Remove the use of the flat files pg_auth and
+ Remove the use of the flat files pg_auth and
pg_database in order to improve performance. (Warning: pgbouncer
and possibly other tools currently suggest referring to the pg_auth
- file for its user database. Such schemes will no longer work.)</emphasis>
+ file for its user database. Such schemes will no longer work.)
</para>
</listitem>
<listitem>
<itemizedlist>
<listitem>
<para>
- <emphasis>Add a Boolean server configuration parameter
+ <emphasis>Provide a parenthesized-options syntax for VACUUM, analogous to
+ that recently adopted for EXPLAIN. This will allow additional
+ options to be implemented in future without having to make them
+ fully-reserved keywords. The old syntax remains available for
+ existing options, however.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis>Add support for an application_name parameter, which is displayed
+ in pg_stat_activity and recorded in log entries.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis>Fix longstanding problems in VACUUM caused by untimely
+ interruptions.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis>Error when a specified connection service is not found in
+ pg_service.conf, instead of ignoring it.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis>Add YAML to list of EXPLAIN formats.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis>Add an EXPLAIN (BUFFERS) option to show buffer-usage statistics.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis>Add a hook to let loadable modules get control at ProcessUtility
+ execution, and use it to extend contrib/pg_stat_statements to track
+ utility commands.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Add a Boolean server configuration parameter
"bonjour" to control whether a Bonjour-enabled
- build actually attempts to advertise itself via Bonjour.</>
+ build actually attempts to advertise itself via Bonjour.
</para>
</listitem>
<listitem>
<para>
- <emphasis>When reloading postgresql.conf, log what parameters actually
- changed.</>
+ When reloading postgresql.conf, log what parameters actually
+ changed.
</para>
</listitem>
<listitem>
<para>
- <emphasis>Make it possibly to specify server configuration parameters
+ Make it possibly to specify server configuration parameters
per user-database combination. Add a \drds command to psql to
- display the settings.</>
+ display the settings.
</para>
</listitem>
<listitem>
<para>
- <emphasis>Allow the collection of statistics on sequences.</>
+ Allow the collection of statistics on sequences.
</para>
</listitem>
<listitem>
<para>
- <emphasis>Increase the maximum value of extra_float_digits to
+ Increase the maximum value of extra_float_digits to
3, and have pg_dump use that value when the backend is new
enough to allow it, because it is possible to need 3 extra
- digits for float4 values (but not for float8 values).</>
+ digits for float4 values (but not for float8 values).
</para>
</listitem>
<listitem>
<itemizedlist>
<listitem>
<para>
- <emphasis>Add ALTER DEFAULT PRIVILEGES command, which allows
+ <emphasis>When querying a table with child tables, do not check permissions
+ on the child tables, only on the parent table. The old behavior was
+ found to be useless and confusing in virtually all cases, and also
+ contrary to the SQL standard.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis>Add a hook to CREATE/ALTER ROLE to allow an external module to
+ check the strength of database passwords, and create a sample
+ implementation of such a hook as a new contrib module
+ "passwordcheck".</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis>Add large object access control.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis>Allow LDAP authentication to operate in search+bind
+ mode, meaning it does a search for the user in the directory
+ first, and then binds with the DN found for this user. This
+ allows for LDAP logins in scenarios where the DN of the user
+ cannot be determined simply by prefix and suffix, such as the
+ case where different users are located in different
+ containers. The old way of authentication can be
+ significantly faster, so it's kept as an option.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Add ALTER DEFAULT PRIVILEGES command, which allows
users to adjust the privileges that will be applied to
- subsequently-created objects.</>
+ subsequently-created objects.
</para>
</listitem>
<listitem>
<para>
- <emphasis>Add GRANT/REVOKE ON ALL TABLES/SEQUENCES/FUNCTIONS IN SCHEMA.
- This makes it easier to manage permissions on database objects.</emphasis>
+ Add GRANT/REVOKE ON ALL TABLES/SEQUENCES/FUNCTIONS IN SCHEMA.
+ This makes it easier to manage permissions on database objects.
</para>
</listitem>
<listitem>
<para>
- <emphasis>Support "samehost" and "samenet" specifications
+ Support "samehost" and "samenet" specifications
in pg_hba.conf. This allows users with dynamic server addresses to run
- PostgreSQL without frequently modifying pg_hba.conf</emphasis>
+ PostgreSQL without frequently modifying pg_hba.conf.
</para>
</listitem>
<listitem>
<itemizedlist>
<listitem>
<para>
- <emphasis>Support POSIX-compatible interpretation of ? as well as {m,n}
- and related constructs in SIMILAR TO, per SQL:2008.</>
+ <emphasis>Remove configuration parameter regex_flavor. It is now always
+ "advanced".</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis>Teach the regular expression functions to do case-insensitive
+ matching and locale-dependent character classification properly
+ when the database encoding is UTF8. This previously only worked
+ correct for single-byte encodings and is still broken for other
+ multibyte encodings.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Support POSIX-compatible interpretation of ? as well as {m,n}
+ and related constructs in SIMILAR TO, per SQL:2008.
</para>
</listitem>
<listitem>
<itemizedlist>
<listitem>
<para>
- <emphasis>Fix encoding handling in binary input function of xml type.</>
+ <emphasis>When doing "ARRAY[...]::domain", where domain is a domain
+ over an array type, we need to check domain constraints. Regression
+ introduced in 8.4.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis>Fix integer-to-bit-string conversions to handle the first
+ fractional byte correctly when the output bit width is wider than
+ the given integer by something other than a multiple of 8 bits.</emphasis>
</para>
</listitem>
<listitem>
<para>
- <emphasis>Tighten binary receive functions so that they reject values
- that the text input functions don't accept either.</>
+ Fix encoding handling in binary input function of xml type.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Tighten binary receive functions so that they reject values
+ that the text input functions don't accept either.
</para>
</listitem>
<listitem>
<itemizedlist>
<listitem>
<para>
- <emphasis>It is now reasonably safe to use pg_ctl to start
- the postmaster from a boot-time script.</emphasis>
+ <emphasis>initdb now selects the encoding SQL_ASCII when the locale specifies
+ US-ASCII. This case previously failed.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis>Add init[db] option to pg_ctl.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ It is now reasonably safe to use pg_ctl to start
+ the postmaster from a boot-time script.
</para>
</listitem>
<listitem>
<itemizedlist>
<listitem>
<para>
- <emphasis>Implement significantly saner behavior when two or
- more psql sessions overlap in their use of the history file.</>
+ <emphasis>In psql, show view definition only with \d+, not with \d.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis>In psql, ignore UTF-8-encoded Unicode byte-order mark at the
+ beginning of a file if the client encoding is UTF-8.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis>Improve psql's tabular display of wrapped-around data by inserting
+ markers in the formerly-always-blank columns just to left and right
+ of the data. "pset linestyle old-ascii" is added to make
+ the previous behavior available if anyone really wants it.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis>Simplify psql's new linestyle behavior to default to
+ linestyle=ascii all the time, rather than hoping we can tell
+ whether the terminal supports UTF-8 characters.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Implement significantly saner behavior when two or
+ more psql sessions overlap in their use of the history file.
</para>
</listitem>
<listitem>
<para>
- <emphasis>Add "pset linestyle ascii/unicode" option to psql,
+ Add "pset linestyle ascii/unicode" option to psql,
allowing our traditional ASCII-art style of table output to
be upgraded to use Unicode box drawing characters if
- desired.</>
+ desired.
</para>
</listitem>
<listitem>
<itemizedlist>
<listitem>
<para>
- <emphasis>Add DO statement to support execution of procedural language
- code without having to create a function for it.</>
+ <emphasis>PL/pgSQL is installed by default.</emphasis>
</para>
</listitem>
<listitem>
<para>
- <emphasis>Support use of function argument names to identify which
+ <emphasis>Remove PL/pgSQL's RENAME declaration, which has
+ bizarre and mostly nonfunctional behavior, and is so little
+ used that no one has been interested in fixing it. To ensure
+ that possible uses are covered, remove the ALIAS declaration's
+ arbitrary restriction that only $n identifiers can be
+ aliased.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis>The PL/pgSQL parser and scanner were reworked to behave much more
+ sanely:</emphasis>
+ </para>
+ <para>
+ <emphasis>A variable reference will only be recognized where it can validly
+ go, ie, a place where a column value or parameter would be legal,
+ instead of the former behavior that would replace any textual match
+ including table names and column aliases (leading to syntax errors
+ later on). PL/pgSQL variable names that match fully-reserved words
+ will now need to be quoted. An the other hand, a number of
+ PL/pgSQL-specific words were de-reserved.</emphasis>
+ </para>
+ <para>
+ <emphasis>The variable resolution behavior is by default not backward
+ compatible, but can be configured; see documentation.</emphasis>
+ </para>
+ <para>
+ <emphasis>Error reporting is much nicer and accurate.</emphasis>
+ </para>
+ <para>
+ <emphasis>The argument of WHERE CURRENT OF can be a PL/pgSQL cursor variable.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis>Add support for anonymous code blocks (DO blocks) to PL/Perl.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis>Support arrays as parameters and return values of PL/Python
+ functions.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis>Python 3 support in PL/Python; behaves more or less unchanged
+ compared to Python 2, but the new language variant is called
+ plpython3u.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Add DO statement to support execution of procedural language
+ code without having to create a function for it.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Support use of function argument names to identify which
actual arguments match which function parameters. The syntax
uses AS, for example funcname(value AS arg1, anothervalue AS
- arg2).</>
+ arg2).
</para>
</listitem>
<listitem>
<para>
- <emphasis>Fix/improve bytea and boolean support in PL/Python. Data type
+ Fix/improve bytea and boolean support in PL/Python. Data type
conversion into and out of PL/Python previously went through
an intermediate string representation, which caused various
discrepancies especially with bytea and boolean data. This is
- now fixed by converting the values directly.</>
+ now fixed by converting the values directly.
</para>
</listitem>
<listitem>
<para>
- <emphasis>PL/Python now accepts Unicode objects where it previously
+ PL/Python now accepts Unicode objects where it previously
only accepted string objects (for example, as return
value). Unicode objects are converted to the PostgreSQL
- server encoding as necessary.</>
+ server encoding as necessary.
</para>
</listitem>
<listitem>
<para>
- <emphasis>Improve error context reporting in PL/Perl, for
- easier debugging.</>
+ Improve error context reporting in PL/Perl, for
+ easier debugging.
</para>
</listitem>
<listitem>
<para>
- <emphasis>PL/pgSQL IN parameters now accept value assignments.</>
+ PL/pgSQL IN parameters now accept value assignments.
</para>
</listitem>
<listitem>
<para>
- <emphasis>Convert a Perl array to a PostgreSQL array when returned by
- set-returning functions as well as non-SRFs.</>
+ Convert a Perl array to a PostgreSQL array when returned by
+ set-returning functions as well as non-SRFs.
</para>
</listitem>
<listitem>
<para>
- <emphasis>Allow cursor commands MOVE FORWARD n, MOVE BACKWARD n,
- MOVE FORWARD ALL, MOVE BACKWARD ALL in PL/pgSQL.</>
+ Allow cursor commands MOVE FORWARD n, MOVE BACKWARD n,
+ MOVE FORWARD ALL, MOVE BACKWARD ALL in PL/pgSQL.
</para>
</listitem>
<listitem>
<itemizedlist>
<listitem>
<para>
- <emphasis>Multiple improvements in contrib/hstore, including
+ <emphasis>Add \shell and \setshell meta commands to pgbench.</emphasis>
+ </para>
+ <para>
+ <emphasis>\shell command runs an external shell command. \setshell also does
+ the same and sets the result to a variable.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Multiple improvements in contrib/hstore, including
raising limits on keys and values, conversions to and from
- records and arrays, and support for GROUP BY and DISTINCT.</emphasis>
+ records and arrays, and support for GROUP BY and DISTINCT.
</para>
</listitem>
<listitem>
<sect3>
<title>Development</title>
<itemizedlist>
+ <listitem>
+ <para>
+ <emphasis>Refactor ECPG grammar so that it uses the core grammar's
+ unreserved_keyword list, minus a few specific words that have to be
+ treated specially. This de-reserves a number of works in ECPG.</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis>Added dynamic cursor names to ECPG.</emphasis>
+ </para>
+ </listitem>
<listitem>
<para>
- <emphasis>Add ECPG function that returns the current transaction status.</>
+ Add ECPG function that returns the current transaction status.
</para>
</listitem>
<listitem>
<para>
- <emphasis>Make ECPG more robust against applications freeing strings.</>
+ Make ECPG more robust against applications freeing strings.
</para>
</listitem>
<listitem>
<para>
- <emphasis>Make libpq reject non-numeric and out-of-range port numbers with a
- suitable error message.</emphasis>
+ Make libpq reject non-numeric and out-of-range port numbers with a
+ suitable error message.
</para>
</listitem>
<listitem>
<itemizedlist>
<listitem>
<para>
- <emphasis>Change the WIN32 API version to be 5.01 (Windows XP), to
- bring in the proper IPv6 headers in newer SDKs.</>
+ <emphasis>Disable triggering failover with a signal in pg_standby on Windows.
+ It never really worked before anyway.</emphasis>
</para>
</listitem>
<listitem>
<para>
- <emphasis>Write to the Windows eventlog in UTF-16, converting the
- message encoding as necessary.</>
+ Change the WIN32 API version to be 5.01 (Windows XP), to
+ bring in the proper IPv6 headers in newer SDKs.
</para>
</listitem>
<listitem>
<para>
- <emphasis>Replace use of the long-deprecated Bonjour API
- DNSServiceRegistrationCreate with the not-so-deprecated
- DNSServiceRegister. The new code will fail on Mac OS X
- releases before 10.3.</>
+ Write to the Windows eventlog in UTF-16, converting the
+ message encoding as necessary.
</para>
</listitem>
<listitem>
<para>
- <emphasis>Install a hopefully-temporary workaround for Mac OS X Snow Leopard
- readdir() bug.</>
+ Replace use of the long-deprecated Bonjour API
+ DNSServiceRegistrationCreate with the not-so-deprecated
+ DNSServiceRegister. The new code will fail on Mac OS X
+ releases before 10.3.
</para>
</listitem>
<listitem>
</itemizedlist>
</sect3>
<sect3>
- <title>Source code, build options</title>
+ <title>Source Code, Build Options</title>
<itemizedlist>
<listitem>
<para>
- <emphasis>Fix inclusions of readline/editline header files so that we
+ <emphasis>configure --enable-thread-safety is now the default (but can still
+ be turned off).</emphasis>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Fix inclusions of readline/editline header files so that we
only attempt to #include the version of history.h that is in
the same directory as the readline.h we are using. This
avoids problems in some scenarios where both readline and
- editline are installed.</>
+ editline are installed.
</para>
</listitem>
<listitem>
<para>
- <emphasis>Derived files that are shipped in the distribution used to be
+ Derived files that are shipped in the distribution used to be
built in the source directory even for out-of-tree
builds. They are now also built in the build tree. This
- should be more convenient for certain developers' workflows.</>
+ should be more convenient for certain developers' workflows.
</para>
</listitem>
<listitem>
<para>
- <emphasis>Translations were updated.</>
+ Translations were updated.
</para>
</listitem>
<listitem>
projects / postgresql / commitdiff