+++ /dev/null
-<!-- doc/src/sgml/release-alpha.sgml -->
-
-<sect1 id="release-9-0-alpha">
- <title>Release 9.0alpha4</title>
- <sect2>
- <title>Overview</title>
- <para>
- PostgreSQL alpha releases are snapshots of development code. They
- are intended to preview and test upcoming features and to provide
- the possibility for early feedback. They should not be used in
- production installations or active development projects. While the
- PostgreSQL code is continuously subject to a number of automated
- and manual tests, alpha releases might have serious bugs. Also
- features may be changed incompatibly or removed at any time during
- the development cycle.
- </para>
- <para>
- The development cycle of a PostgreSQL major release alternates
- between periods of development and periods of integration work,
- called commit fests, normally one month each. Alpha releases are
- planned to be produced at the end of every commit fest, thus every
- two months. Since the first commit fest starts within a month from
- the beginning of development altogether, early alpha releases are
- not indicative of the likely feature set of the final release.
- </para>
- <para>
- The release notes below highlight user visible changes and new
- features. There are normally numerous bug fixes and performance
- improvements in every new snapshot of PostgreSQL, and it would be
- too bulky to attempt to list them all. Note that many bug fixes are
- also backported to stable releases of PostgreSQL, and you should be
- using those if you are looking for bug-fix-only upgrades for your
- current installations.
- </para>
- <para>
- The release notes are cumulative over all alpha releases. Items
- that are new in the latest alpha release
- are <emphasis>emphasized</emphasis>.
- </para>
- </sect2>
- <sect2>
- <title>Migration</title>
- <para>
- To upgrade from any release to an alpha release or from an alpha
- release to any other release will most likely require a
- dump/restore upgrade procedure. It may happen that this is not
- necessary in particular cases, but that is not verified beforehand.
- (The server will warn you in any case when a dump/restore is
- necessary if you attempt to use it with an old data directory.)
- Note, however, that the dump/restore upgrade procedure is expected
- to work for alpha releases, and problems in this area should be
- reported.
- </para>
- </sect2>
- <sect2>
- <title>Testing</title>
- <para>
- The primary reason we release alphas is to get users to test new
- features as early as possible. If you are interested in helping
- with organized testing, please see
- <ulink url="http://wiki.postgresql.org/wiki/HowToBetaTest">the
- testing information page</ulink>.
- </para>
- </sect2>
- <sect2>
- <title>Changes</title>
- <sect3>
- <title>SQL Features</title>
- <itemizedlist>
- <listitem>
- <para>
- <emphasis>Disallow comments on columns of relation types
- other than tables, views, and composite types, that is,
- sequences and TOAST tables.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Adjust naming of indexes and their columns. Index
- expression columns are now named after the FigureColname
- result for their expressions, rather than always being
- "pg_expression_N". Digits are appended to this name if
- needed to make the column name unique within the index.
- Default names for indexes and associated constraints now
- include the column names of all their columns, not only the
- first one as in previous practice.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Allow the index name to be omitted in CREATE INDEX,
- causing the system to choose an index name the same as it
- would do for an unnamed index constraint. A necessary
- side-effect is to promote the word CONCURRENTLY to a more
- reserved status; it can't be a table/column/index name
- anymore unless quoted.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Improve the handling of SET CONSTRAINTS commands by
- having them search pg_constraint before searching pg_trigger.
- This allows saner handling of corner cases.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Typed table feature; this adds the CREATE TABLE
- name OF type command.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Tighten integrity checks on ALTER TABLE ... RENAME
- COLUMN in inheritance hierarchies.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Replace the pg_listener-based LISTEN/NOTIFY
- mechanism with an in-memory queue. In addition, add support
- for a "payload" string to be passed along with each notify
- event.</emphasis>
- </para>
- <para>
- <emphasis>This implementation should be significantly more
- efficient than the old one, and is also more compatible with
- Hot Standby usage. There is not yet any facility for HS
- standby servers to receive notifications generated on the master,
- although such a thing is possible in future.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Have SELECT and CREATE TABLE AS queries return a
- row count. While this is invisible in psql, other
- interfaces, like libpq, make this value visible.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Extend the set of frame options supported for
- window functions. This allows the frame to start from
- CURRENT ROW (in either RANGE or ROWS mode), and it also adds
- support for ROWS n PRECEDING and ROWS n FOLLOWING start and
- end points.</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).
- </para>
- </listitem>
- <listitem>
- <para>
- Remove previously deprecated configuration
- parameter add_missing_from. The system now always behaves as
- though add_missing_from were off.
- </para>
- </listitem>
- <listitem>
- <para>
- Performance and behavioral improvements in UPDATE,
- DELETE, and SELECT FOR UPDATE/SHARE queries with joins.
- Fix various corner cases that could have resulted 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.
- </para>
- </listitem>
- <listitem>
- <para>
- Fix SELECT FOR UPDATE/SHARE in conjunction with LIMIT.
- Previously, it could return fewer rows than the limit specified.
- </para>
- </listitem>
- <listitem>
- <para>
- Add a WHEN clause to CREATE TRIGGER, allowing a boolean expression
- to be checked to determine whether the trigger should be fired.
- </para>
- <para>
- 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.
- </para>
- </listitem>
- <listitem>
- <para>
- 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.
- </para>
- </listitem>
- <listitem>
- <para>
- 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.
- </para>
- <para>
- Behavioral change: formerly, agg(DISTINCT x) dropped null values of
- x unconditionally. Now, it does so only if the aggregate's transition
- function is strict; otherwise nulls are treated as DISTINCT
- normally would, i.e., you get one copy.
- </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.
- </para>
- </listitem>
- <listitem>
- <para>
- Define a new, more extensible syntax for COPY options
- in order to support additional COPY options in the future.
- </para>
- </listitem>
- <listitem>
- <para>
- 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.
- </para>
- </listitem>
- <listitem>
- <para>
- Fix bug with nested WITH RECURSIVE statements.
- </para>
- </listitem>
- <listitem>
- <para>
- Add surrogate pair support for U& string and identifier
- syntax.
- </para>
- </listitem>
- <listitem>
- <para>
- Add Unicode escapes in E'...' strings.
- </para>
- </listitem>
- <listitem>
- <para>
- DROP COLUMN and DROP CONSTRAINT now support an IF EXISTS clause so
- that users can avoid fatal errors when running repeatable scripts.
- </para>
- </listitem>
- <listitem>
- <para>
- UNIQUE constraints can now be DEFERRABLE. This is primarily useful
- for incremental updates of numerical keys, e.g. "ID = ID +
- 1"
- </para>
- </listitem>
- <listitem>
- <para>
- Allow parentheses around the query expression that follows a WITH
- clause.
- </para>
- </listitem>
- <listitem>
- <para>
- INFORMATION_SCHEMA, a catalog of standard views of database
- objects, has been updated to the SQL:2008 standard.
- </para>
- </listitem>
- <listitem>
- <para>
- Change character_octet_length to more sensible values in
- INFORMATION_SCHEMA.
- </para>
- </listitem>
- <listitem>
- <para>
- Allow * as parameter for FORCE QUOTE for COPY CSV, so that all
- columns will be quoted.
- </para>
- </listitem>
- </itemizedlist>
- </sect3>
- <sect3>
- <title>Performance</title>
- <itemizedlist>
- <listitem>
- <para>
- <emphasis>Support "x IS NOT NULL" clauses as index-scan
- conditions.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>When estimating the selectivity of an inequality
- "column > constant" or "column < constant", and the
- comparison value is in the first or last histogram bin or
- outside the histogram entirely, try to fetch the actual
- column min or max value using an index scan (if there is an
- index on the column). If successful, replace the lower or
- upper histogram bound with that value before carrying on with
- the estimate. This limits the estimation error caused by
- moving min/max values when the comparison value is close to
- the min or max.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Generic implementation of red-black binary tree.
- For now, only GIN uses it during index creation. Using
- self-balanced tree greatly speeds up index creation in corner
- cases with preordered data.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- Allow rewriting forms of ALTER TABLE to skip WAL
- logging.
- </para>
- </listitem>
- <listitem>
- <para>
- Speed up INFORMATION_SCHEMA's privilege views.
- </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.
- </para>
- </listitem>
- <listitem>
- <para>
- 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.
- </para>
- </listitem>
- <listitem>
- <para>
- 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.)
- </para>
- </listitem>
- <listitem>
- <para>
- EXPLAIN allows output of plans in XML, JSON, or YAML format for automated
- processing of explain plans by analysis or visualization tools.
- </para>
- </listitem>
- <listitem>
- <para>
- EXPLAIN now supports the use of generic options in EXPLAIN ( option
- value, ... ) format, which permits the creation of additional
- EXPLAIN options.
- </para>
- </listitem>
- <listitem>
- <para>
- ALTER TABLE ... ALTER COLUMN ... SET STATISTICS DISTINCT allows
- users to manually tweak the number of distinct values estimated for
- a column, to fix cases where ANALYZE estimates are incorrect.
- </para>
- </listitem>
- <listitem>
- <para>
- Make GEQO's planning deterministic by having it start from a
- predictable random number seed each time.
- </para>
- </listitem>
- <listitem>
- <para>
- Rewrite GEQO's gimme_tree function so that it always finds a legal
- join sequence. Previously, it could have failed to produce a plan
- in some cases.
- </para>
- </listitem>
- <listitem>
- <para>
- Tweak TOAST code so that columns marked with MAIN storage strategy
- are not forced out-of-line unless that is necessary to make the row
- fit on a page. Previously, they were forced out-of-line if needed
- to get the row down to the default target size (1/4th page).
- </para>
- </listitem>
- <listitem>
- <para>
- Simplify the forms foo <> true and foo <> false to foo
- = false and foo = true during query optimization.
- </para>
- </listitem>
- <listitem>
- <para>
- Avoid per-send() system calls to manage SIGPIPE in libpq, if the
- platform provides either sockopt(SO_NOSIGPIPE) or the MSG_NOSIGNAL
- flag to send().
- </para>
- </listitem>
- </itemizedlist>
- </sect3>
- <sect3>
- <title>Administration and Monitoring</title>
- <itemizedlist>
- <listitem>
- <para>
- <emphasis>Add the ability to store inheritance-tree
- statistics in pg_statistic, and teach ANALYZE to compute such
- stats for tables that have subclasses.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Revise pgstat's tracking of tuple changes to
- improve the reliability of decisions about when to
- auto-analyze. The previous code depended on n_live_tuples +
- n_dead_tuples - last_anl_tuples, where all three of these
- numbers could be bad estimates from ANALYZE itself. Even
- worse, in the presence of a steady flow of HOT updates and
- matching HOT-tuple reclamations, auto-analyze might never
- trigger at all, even if all three numbers are exactly right,
- because n_dead_tuples could hold steady.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Support ALTER TABLESPACE name SET/RESET (
- tablespace_options ), currently supporting seq_page_cost and
- random_page_cost as parameters.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>New faster implementation of VACUUM FULL. The old
- idiom of using CLUSTER instead of VACUUM FULL for speed is
- now obsolete.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Add buffer access counters to
- pg_stat_statements.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Add some simple support and documentation for using
- process-specific oom_adj settings to prevent the postmaster
- from being OOM-killed on Linux systems.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Place tablespace directories in their own
- subdirectory so pg_migrator can upgrade clusters without
- renaming the tablespace directories.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Introduce Streaming Replication.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Add pg_table_size() and pg_indexes_size() to
- provide more user-friendly wrappers around the
- pg_relation_size() function.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Add pg_stat_reset_shared('bgwriter') to reset the
- cluster-wide shared statistics of the bgwriter.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Replace ALTER TABLE ... SET STATISTICS DISTINCT
- with a more general mechanism. Attributes can now have
- options, just as relations and tablespaces do, and the
- reloptions code is used to parse, validate, and store
- them.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Fix longstanding gripe that we check for
- 0000000001.history at start of archive recovery, even when we
- know it is never present.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Make standby server continuously retry restoring
- the next WAL segment with restore_command, if the connection
- to the primary server is lost. This ensures that the standby
- can recover automatically, if the connection is lost for a
- long time and standby falls behind so much that the required
- WAL segments have been archived and deleted in the
- master.</emphasis>
- </para>
- <para>
- <emphasis>This also makes standby_mode useful without
- streaming replication; the server will keep retrying
- restore_command every few seconds until the trigger file is
- found. That's the same basic functionality pg_standby
- offers, but without the bells and whistles.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Add functions to reset the statistics counter for a
- single table/index or a single function.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Augment EXPLAIN output with more details on Hash
- nodes.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Reindexing shared system catalogs is now fully
- transactional and crash-safe.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- Allow read-only connections during recovery, also
- known as Hot Standby. This provides a built-in master-standby
- replication solution.
- </para>
- </listitem>
- <listitem>
- <para>
- 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.
- </para>
- </listitem>
- <listitem>
- <para>
- Add support for an application_name parameter, which is displayed
- in pg_stat_activity and recorded in log entries.
- </para>
- </listitem>
- <listitem>
- <para>
- Fix longstanding problems in VACUUM caused by untimely
- interruptions.
- </para>
- </listitem>
- <listitem>
- <para>
- Add YAML to list of EXPLAIN formats.
- </para>
- </listitem>
- <listitem>
- <para>
- Add an EXPLAIN (BUFFERS) option to show buffer-usage statistics.
- </para>
- </listitem>
- <listitem>
- <para>
- 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.
- </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.
- </para>
- </listitem>
- <listitem>
- <para>
- When reloading postgresql.conf, log what parameters actually
- changed.
- </para>
- </listitem>
- <listitem>
- <para>
- Make it possibly to specify server configuration parameters
- per user-database combination. Add a \drds command to psql to
- display the settings.
- </para>
- </listitem>
- <listitem>
- <para>
- Allow the collection of statistics on sequences.
- </para>
- </listitem>
- <listitem>
- <para>
- 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).
- </para>
- </listitem>
- <listitem>
- <para>
- Add the ability to include the SQLSTATE error code of any error
- messages in the PostgreSQL activity log with the new
- log_line_prefix placeholder %e.
- </para>
- </listitem>
- <listitem>
- <para>
- Show the exact value being complained of in
- unique-constraint-violation error messages, including unique-index
- build failures.
- </para>
- </listitem>
- </itemizedlist>
- </sect3>
- <sect3>
- <title>Security</title>
- <itemizedlist>
- <listitem>
- <para>
- <emphasis>Add support for RADIUS authentication.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- 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.
- </para>
- </listitem>
- <listitem>
- <para>
- 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".
- </para>
- </listitem>
- <listitem>
- <para>
- Add large object access control.
- </para>
- </listitem>
- <listitem>
- <para>
- 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.
- </para>
- </listitem>
- <listitem>
- <para>
- Add ALTER DEFAULT PRIVILEGES command, which allows
- users to adjust the privileges that will be applied to
- subsequently-created objects.
- </para>
- </listitem>
- <listitem>
- <para>
- Add GRANT/REVOKE ON ALL TABLES/SEQUENCES/FUNCTIONS IN SCHEMA.
- This makes it easier to manage permissions on database objects.
- </para>
- </listitem>
- <listitem>
- <para>
- 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.
- </para>
- </listitem>
- <listitem>
- <para>
- New has_sequence_privilege() functions allow you to check sequence
- privileges for a given ROLE.
- </para>
- </listitem>
- </itemizedlist>
- </sect3>
- <sect3>
- <title>Built-In Functions</title>
- <itemizedlist>
- <listitem>
- <para>
- <emphasis>Fix 3-parameter form of bit substring() to throw
- error for negative length, as required by SQL
- standard.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Add get_bit/set_bit functions for bit strings,
- paralleling those for bytea, and implement OVERLAY() for bit
- strings and bytea.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Add string_agg aggregate functions. The
- one-argument version concatenates the input values into a
- string. The two-argument version also does the same thing,
- but inserts delimiters between elements.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Honor to_char() "FM" specification in YYY, YY, and
- Y; it was already honored by YYYY.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- Remove configuration parameter regex_flavor. It is now always
- "advanced".
- </para>
- </listitem>
- <listitem>
- <para>
- 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
- correctly for single-byte encodings. It is still broken for other
- multibyte encodings.
- </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>
- <para>
- The to_char() formatting functions now supports EEEE (scientific
- notation).
- </para>
- </listitem>
- <listitem>
- <para>
- Use floor() not rint() when reducing precision of fractional
- seconds in timestamp_trunc, timestamptz_trunc, and interval_trunc()
- for the float-datetime case. This improves accuracy of time
- calculations.
- </para>
- </listitem>
- <listitem>
- <para>
- Fix ancient bug in handling of to_char() modifier 'TH', when used
- with HH.
- </para>
- </listitem>
- </itemizedlist>
- </sect3>
- <sect3>
- <title>Data Types</title>
- <itemizedlist>
- <listitem>
- <para>
- <emphasis>Allow enums to be created with zero labels, for use
- during binary upgrade.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- When doing "ARRAY[...]::domain", where domain is a domain
- over an array type, we need to check domain constraints. Regression
- introduced in 8.4.
- </para>
- </listitem>
- <listitem>
- <para>
- 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.
- </para>
- </listitem>
- <listitem>
- <para>
- 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>
- <para>
- New hex-string input and output format options for type bytea. Hex
- output format is enabled by default, which is an incompatible
- change. See the new bytea_output parameter if you need to restore
- compatibility.
- </para>
- </listitem>
- <listitem>
- <para>
- Adds prefix support for text search synonym dictionary, allowing
- creation of synonyms on partial matches.
- </para>
- </listitem>
- </itemizedlist>
- </sect3>
- <sect3>
- <title>Server Tools</title>
- <itemizedlist>
- <listitem>
- <para>
- initdb now selects the encoding SQL_ASCII when the locale specifies
- US-ASCII. This case previously failed.
- </para>
- </listitem>
- <listitem>
- <para>
- Add init[db] option to pg_ctl.
- </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>
- <para>
- pg_dump/pg_restore --clean now drops large objects.
- </para>
- </listitem>
- <listitem>
- <para>
- Modify parallel pg_restore ordering logic to avoid a potential
- O(N^2) slowdown for some complex databases.
- </para>
- </listitem>
- </itemizedlist>
- </sect3>
- <sect3>
- <title>libpq</title>
- <itemizedlist>
- <listitem>
- <para>
- <emphasis>Add user-specific .pg_service.conf file.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Add new escaping functions PQescapeLiteral and
- PQescapeIdentifier.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Introduce two new libpq connection functions,
- PQconnectdbParams and PQconnectStartParams, which are
- analogous to PQconnectdb and PQconnectStart respectively, but
- accept two NULL-terminated arrays, keywords and values,
- rather than conninfo strings. This avoids the need to build
- the conninfo string in cases where it might be inconvenient
- to do so.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- Throw error when a specified connection service name is not
- found in pg_service.conf, instead of ignoring it.
- </para>
- </listitem>
- <listitem>
- <para>
- Make libpq reject non-numeric and out-of-range port numbers with a
- suitable error message.
- </para>
- </listitem>
- </itemizedlist>
- </sect3>
- <sect3>
- <title>psql</title>
- <itemizedlist>
- <listitem>
- <para>
- <emphasis>Allow psql variables to be interpolated with
- literal or identifier escaping.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- In psql, show view definition only with \d+, not with \d.
- </para>
- </listitem>
- <listitem>
- <para>
- In psql, ignore UTF-8-encoded Unicode byte-order mark at the
- beginning of a file if the client encoding is UTF-8.
- </para>
- </listitem>
- <listitem>
- <para>
- 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.
- </para>
- </listitem>
- <listitem>
- <para>
- 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.
- </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>
- 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.
- </para>
- </listitem>
- <listitem>
- <para>
- Have \d show child tables that inherit from the specified parent
- </para>
- </listitem>
- <listitem>
- <para>
- psql now shows the index methods in \di
- </para>
- </listitem>
- </itemizedlist>
- </sect3>
-
- <sect3>
- <title>Procedural Languages</title>
- <sect4>
- <title>PL/pgSQL</title>
- <itemizedlist>
- <listitem>
- <para>
- <emphasis>Add "USING expressions" option to PL/pgSQL's OPEN
- cursor FOR EXECUTE.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- PL/pgSQL is installed by default.
- </para>
- </listitem>
- <listitem>
- <para>
- 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.
- </para>
- </listitem>
- <listitem>
- <para>
- The PL/pgSQL parser and scanner were reworked to behave much more
- sanely:
- </para>
- <para>
- 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).
- </para>
- <para>
- When a name could refer either to a PL/pgSQL variable or a
- table column, PL/pgSQL formerly always assumed the variable was
- meant, sometimes resulting in surprising behavior. Now, PL/pgSQL
- can assume the variable is meant, or assume the table column is
- meant, or throw an error in ambiguous cases. For safety the default
- is to throw error. To configure this see <link
- linkend="plpgsql-var-subst">the PL/pgSQL documentation</link>.
- </para>
- <para>
- Error reporting is much nicer: it no longer shows edited
- versions of statements that look significantly different from what
- you wrote.
- </para>
- <para>
- Note that this change affects the set of keywords that are
- reserved in PL/pgSQL (i.e., cannot be the name of a PL/pgSQL
- variable). Now, all keywords shown as reserved in <link
- linkend="sql-keywords-appendix">Appendix C</link> are reserved for
- PL/pgSQL purposes as well. However, many PL/pgSQL-only keywords
- that were formerly treated as reserved no longer are. As in regular
- SQL, you can double-quote a variable's name if you want to use a
- name that conflicts with a reserved keyword.
- </para>
- </listitem>
- <listitem>
- <para>
- PL/pgSQL IN parameters now accept value assignments.
- </para>
- </listitem>
- <listitem>
- <para>
- Allow cursor commands MOVE FORWARD n, MOVE BACKWARD n,
- MOVE FORWARD ALL, MOVE BACKWARD ALL in PL/pgSQL.
- </para>
- </listitem>
- <listitem>
- <para>
- PL/pgSQL functions can now better cope with row types
- containing dropped columns.
- </para>
- </listitem>
- </itemizedlist>
- </sect4>
-
- <sect4>
- <title>PL/Perl</title>
- <itemizedlist>
- <listitem>
- <para>
- <emphasis>Add utility functions to PL/Perl: quote_literal,
- quote_nullable, quote_ident, encode_bytea, decode_bytea,
- looks_like_number, encode_array_literal,
- encode_array_constructor.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Add plperl.on_plperl_init, plperl.on_plperlu_init,
- and plperl.on_init settings for startup code.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Allow (ineffective) use of "require". If the
- required module is not already loaded then it dies. So "use
- strict;" now works in PL/Perl.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Pre-load the feature module if Perl >= 5.10.
- So "use feature :5.10;" now works in PL/Perl.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Stored procedure subs are now given names. The
- names are not visible in ordinary use, but they make tools
- like Devel::NYTProf and Devel::Cover much more
- useful.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Handle END blocks in PL/Perl.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Clean up package namespace use and use of Safe.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Change log level of Perl warnings from NOTICE to
- WARNING.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- Add support for anonymous code blocks (DO blocks) to PL/Perl.
- </para>
- </listitem>
- <listitem>
- <para>
- Improve error context reporting in PL/Perl, for
- easier debugging.
- </para>
- </listitem>
- <listitem>
- <para>
- Convert a Perl array to a PostgreSQL array when returned by
- set-returning functions as well as non-SRFs.
- </para>
- </listitem>
- </itemizedlist>
- </sect4>
-
- <sect4>
- <title>PL/Python</title>
- <itemizedlist>
- <listitem>
- <para>
- <emphasis>Improved printing of Python exceptions in
- PL/Python.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Add PL/Python DO handler.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- Support arrays as parameters and return values of PL/Python
- functions.
- </para>
- </listitem>
- <listitem>
- <para>
- Add Python 3 support to PL/Python. It behaves more or less
- unchanged compared to Python 2, but the new language variant is
- called plpython3u.
- </para>
- </listitem>
- <listitem>
- <para>
- 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.
- </para>
- </listitem>
- <listitem>
- <para>
- 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.
- </para>
- </listitem>
- <listitem>
- <para>
- Improve error context reporting in PL/Python, for easier
- debugging.
- </para>
- </listitem>
- <listitem>
- <para>
- Greatly expand the regression testing for PL/Python.
- </para>
- </listitem>
- </itemizedlist>
- </sect4>
- </sect3>
-
- <sect3>
- <title>Additional Supplied Modules</title>
- <itemizedlist>
- <listitem>
- <para>
- <emphasis>Add query text to auto_explain output.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- Add \shell and \setshell meta commands to pgbench.
- </para>
- <para>
- \shell runs an external shell command. \setshell
- does the same and assigns the result to a variable.
- </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.
- </para>
- </listitem>
- <listitem>
- <para>
- pgbench is now multi-threaded, allowing it to use multiple CPU's
- for its client connections, and to do more realistic workload
- testing.
- </para>
- </listitem>
- <listitem>
- <para>
- Added the ability to retrieve asynchronous notifications using
- dblink, via the addition of the function dblink_get_notify().
- </para>
- </listitem>
- <listitem>
- <para>
- Added matchorig, matchsynonyms, and keepsynonyms options to
- contrib/dict_xsyn.
- </para>
- </listitem>
- <listitem>
- <para>
- Added contrib/unaccent.
- </para>
- </listitem>
- </itemizedlist>
- </sect3>
- <sect3>
- <title>ECPG</title>
- <itemizedlist>
- <listitem>
- <para>
- <emphasis>Add sqlda support in both native and compatibility
- mode.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Fix SQL3 type return value: For non-SQL3 types ECPG
- used to return -OID. This will break if there are enough OIDs
- to fill the namespace. Therefore we play it safe and return
- 0 if there is no OID->SQL3 type mapping available.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Make char the default sqlda type.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Add DESCRIBE [OUTPUT] statement.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Add out-of-scope cursor support to native mode.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- 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 words in ECPG.
- </para>
- </listitem>
- <listitem>
- <para>
- Added dynamic cursor names to ECPG.
- </para>
- </listitem>
- <listitem>
- <para>
- Add ECPG function that returns the current transaction status.
- </para>
- </listitem>
- <listitem>
- <para>
- Make ECPG more robust against applications freeing strings.
- </para>
- </listitem>
- <listitem>
- <para>
- ECPG now includes a STRING datatype for Informix compatibility
- mode.
- </para>
- </listitem>
- </itemizedlist>
- </sect3>
- <sect3>
- <title>Ports</title>
- <itemizedlist>
- <listitem>
- <para>
- <emphasis>Add basic build support for Visual Studio 2008,
- without resorting to generating the build files for 2005 and
- then converting them.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Added support for 64-bit Windows platforms.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- Disable triggering failover with a signal in pg_standby on Windows.
- It never really worked before anyway.
- </para>
- </listitem>
- <listitem>
- <para>
- 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>
- Write to the Windows eventlog in UTF-16, converting the
- message encoding as necessary.
- </para>
- </listitem>
- <listitem>
- <para>
- 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>
- <para>
- Reserve the shared memory region during backend startup on Windows,
- so that memory allocated by starting third party DLLs doesn't end
- up conflicting with it. Hopefully this solves the long-time issue
- with "could not reattach to shared memory" errors on
- Win32.
- </para>
- </listitem>
- <listitem>
- <para>
- Add s_lock support for SuperH architecture (not well tested).
- </para>
- </listitem>
- </itemizedlist>
- </sect3>
- <sect3>
- <title>Source Code, Build Options</title>
- <itemizedlist>
- <listitem>
- <para>
- <emphasis>Improve PGXS makefile system to allow the module's
- makefile to specify where to install DATA and DOCS files.
- This is mainly intended to allow versioned installation, eg,
- install into contrib/fooM.N/ rather than directly into
- contrib/.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Get rid of the need for manual maintenance of the
- initial contents of pg_attribute, by having genbki.pl derive
- the information from the various catalog header files. This
- greatly simplifies modification of the "bootstrapped"
- catalogs. This patch finally kills genbki.sh and
- Gen_fmgrtab.sh; we now rely entirely on Perl scripts for
- those build steps. To avoid creating a Perl build dependency
- where there was not one before, they will be built and
- shipped in tarballs.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Move the default configuration for the MSVC build
- system to config_default.pl, and allow using config.pl to
- override the defaults.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Make configure check the version of Perl we're
- building with, and reject versions < 5.8.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Remove all support for working around on systems
- that don't provide a working 64-bit integer type.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- <emphasis>Add new make targets "world", "install-world" and
- "installcheck-world" to build, install and check just about
- everything. In addition to everything built installed and
- tested by all, install and installcheck targets, these build
- HTML documentation, build and test contrib, and test
- procedural languages and ECPG.</emphasis>
- </para>
- </listitem>
- <listitem>
- <para>
- configure --enable-thread-safety is now the default (but can still
- be turned off).
- </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.
- </para>
- </listitem>
- <listitem>
- <para>
- 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 built in the build tree. This
- should be more convenient for certain developers' workflows.
- </para>
- </listitem>
- <listitem>
- <para>
- Functions which conflict with C++ reserved words have been renamed,
- making backend header files now safe to use with C++ libraries.
- </para>
- </listitem>
- <listitem>
- <para>
- Add man pages for SPI functions.
- </para>
- </listitem>
- <listitem>
- <para>
- Upgrade to Autoconf 2.63 (not relevant to users of distribution
- tarballs).
- </para>
- </listitem>
- <listitem>
- <para>
- Minimum version of Flex is now 2.5.31, to support reentrant
- scanners (not relevant to users of distribution tarballs).
- </para>
- </listitem>
- <listitem>
- <para>
- Documentation build rules have been improved. The generated
- documentation files are now shipped "loose", not in
- sub-tarballs.
- </para>
- </listitem>
- <listitem>
- <para>
- New toolchain to generate man pages. From now on, the man pages
- will be current in every release.
- </para>
- </listitem>
- <listitem>
- <para>
- Code-coverage testing support now extends to the entire source
- tree, not only src/backend/.
- </para>
- </listitem>
- <listitem>
- <para>
- Make the core scanner re-entrant, along with additional fixes that
- will let it be used directly by PL/pgSQL.
- </para>
- </listitem>
- </itemizedlist>
- </sect3>
- </sect2>
-</sect1>
projects / postgresql / commitdiff