<!-- doc/src/sgml/release-16.sgml -->
<!-- See header comment in release.sgml about typical markup -->
<sect1 id="release-16">
<title>Release 16</title>
<formalpara>
<title>Release date:</title>
<para>2023-09-14</para>
</formalpara>
<sect2 id="release-16-highlights">
<title>Overview</title>
<para>
<productname>PostgreSQL</productname> 16 contains many new features
and enhancements, including:
</para>
<itemizedlist>
<listitem>
<para>
Allow parallelization of <literal>FULL</literal> and internal right <literal>OUTER</literal> hash joins
</para>
</listitem>
<listitem>
<para>
Allow logical replication from standby servers
</para>
</listitem>
<listitem>
<para>
Allow logical replication subscribers to apply large transactions in parallel
</para>
</listitem>
<listitem>
<para>
Allow monitoring of <acronym>I/O</acronym> statistics using the new <structname>pg_stat_io</structname> view
</para>
</listitem>
<listitem>
<para>
Add <acronym>SQL/JSON</acronym> constructors and identity functions
</para>
</listitem>
<listitem>
<para>
Improve performance of vacuum freezing
</para>
</listitem>
<listitem>
<para>
Add support for regular expression matching of user and database names in <filename>pg_hba.conf</filename>, and user names in <filename>pg_ident.conf</filename>
</para>
</listitem>
</itemizedlist>
<para>
The above items and other new features of
<productname>PostgreSQL</productname> 16 are explained in more detail
in the sections below.
</para>
</sect2>
<sect2 id="release-16-migration">
<title>Migration to Version 16</title>
<para>
A dump/restore using <xref linkend="app-pg-dumpall"/> or use of
<xref linkend="pgupgrade"/> or logical replication is required for
those wishing to migrate data from any previous release. See <xref
linkend="upgrading"/> for general information on migrating to new
major releases.
</para>
<para>
Version 16 contains a number of changes that may affect compatibility
with previous releases. Observe the following incompatibilities:
</para>
<itemizedlist>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-01-01 [d747dc85a] In plpgsql, don't preassign portal names to bound cursor
-->
<listitem>
<para>
Change assignment rules for <link
linkend="plpgsql-open-bound-cursor"><application>PL/pgSQL</application></link>
bound cursor variables (Tom Lane)
</para>
<para>
Previously, the string value of such variables
was set to match the variable name during cursor
assignment; now it will be assigned during <link
linkend="plpgsql-cursor-opening"><command>OPEN</command></link>,
and will not match the variable name. To restore the previous
behavior, assign the desired portal name to the cursor variable
before <command>OPEN</command>.
</para>
</listitem>
<!--
Author: Daniel Gustafsson <dgustafsson@postgresql.org>
2023-02-24 [d95952325] Disallow NULLS NOT DISTINCT indexes for primary keys
-->
<listitem>
<para>
Disallow <link linkend="sql-createindex"><literal>NULLS NOT
DISTINCT</literal></link> indexes for primary keys (Daniel
Gustafsson)
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2022-07-19 [2cbc3c17a] Rework logic and simplify syntax of REINDEX DATABASE/SYS
Author: Michael Paquier <michael@paquier.xyz>
2022-07-26 [0a5f06b84] Fix a few issues with REINDEX grammar
-->
<listitem>
<para>
Change <link linkend="sql-reindex"><command>REINDEX
DATABASE</command></link> and <link
linkend="app-reindexdb"><application>reindexdb</application></link>
to not process indexes on system catalogs (Simon Riggs)
</para>
<para>
Processing such indexes is still possible using <command>REINDEX
SYSTEM</command> and <link linkend="app-reindexdb"><command>reindexdb
--system</command></link>.
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-01-11 [8bf6ec3ba] Improve handling of inherited GENERATED expressions.
-->
<listitem>
<para>
Tighten <link
linkend="ddl-generated-columns"><literal>GENERATED</literal></link>
expression restrictions on inherited and partitioned tables (Amit
Langote, Tom Lane)
</para>
<para>
Columns of parent/partitioned and child/partition tables must all
have the same generation status, though now the actual generation
expressions can be different.
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2023-03-14 [5c1b66280] Rework design of functions in pg_walinspect
-->
<listitem>
<para>
Remove <link
linkend="pgwalinspect"><application>pg_walinspect</application></link>
functions
<function>pg_get_wal_records_info_till_end_of_wal()</function>
and <function>pg_get_wal_stats_till_end_of_wal()</function>
(Bharath Rupireddy)
</para>
</listitem>
<!--
Author: David Rowley <drowley@postgresql.org>
2023-02-15 [5352ca22e] Rename force_parallel_mode to debug_parallel_query
Author: David Rowley <drowley@postgresql.org>
2023-04-14 [0981846b9] Remove old GUC name mapping for "force_parallel_mode"
-->
<listitem>
<para>
Rename server variable
<varname>force_parallel_mode</varname> to <link
linkend="guc-debug-parallel-query"><varname>debug_parallel_query</varname></link>
(David Rowley)
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2022-12-02 [b23cd185f] Remove logic for converting a table to a view.
-->
<listitem>
<para>
Remove the ability to <link linkend="sql-createview">create
views</link> manually with <literal>ON SELECT</literal> rules
(Tom Lane)
</para>
</listitem>
<!--
Author: Andres Freund <andres@anarazel.de>
2023-04-24 [1118cd37e] Remove vacuum_defer_cleanup_age
-->
<listitem>
<para>
Remove the server variable
<varname>vacuum_defer_cleanup_age</varname> (Andres Freund)
</para>
<para>
This has been unnecessary since <link
linkend="guc-hot-standby-feedback"><varname>hot_standby_feedback</varname></link>
and <link linkend="streaming-replication-slots">replication
slots</link> were added.
</para>
</listitem>
<!--
Author: Thomas Munro <tmunro@postgresql.org>
2022-11-29 [cd4329d93] Remove promote_trigger_file.
-->
<listitem>
<para>
Remove server variable <varname>promote_trigger_file</varname>
(Simon Riggs)
</para>
<para>
This was used to promote a standby to primary, but is now more easily
accomplished with <link linkend="app-pg-ctl"><literal>pg_ctl
promote</literal></link> or <link
linkend="functions-recovery-control-table"><function>pg_promote()</function></link>.
</para>
</listitem>
<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2023-06-07 [b0f6c4371] Remove read-only server settings lc_collate and lc_ctype
-->
<listitem>
<para>
Remove read-only server variables <varname>lc_collate</varname>
and <varname>lc_ctype</varname> (Peter Eisentraut)
</para>
<para>
Collations and locales can vary between databases so having them
as read-only server variables was unhelpful.
</para>
</listitem>
<!--
Author: Robert Haas <rhaas@postgresql.org>
2022-08-25 [e3ce2de09] Allow grant-level control of role inheritance behavior.
-->
<listitem>
<para>
Role inheritance now controls the default
inheritance status of member roles added during <link
linkend="sql-grant"><command>GRANT</command></link> (Robert Haas)
</para>
<para>
The role's default inheritance behavior can be overridden with the
new <command>GRANT ... WITH INHERIT</command> clause. This allows
inheritance of some roles and not others because the members'
inheritance status is set at <command>GRANT</command> time.
Previously the inheritance status of member roles was controlled
only by the role's inheritance status, and changes to a role's
inheritance status affected all previous and future member roles.
</para>
</listitem>
<!--
Author: Robert Haas <rhaas@postgresql.org>
2023-01-10 [cf5eb37c5] Restrict the privileges of CREATEROLE users.
Author: Robert Haas <rhaas@postgresql.org>
2023-01-24 [f1358ca52] Adjust interaction of CREATEROLE with role properties.
-->
<listitem>
<para>
Restrict the privileges of <link
linkend="sql-createrole"><literal>CREATEROLE</literal></link>
and its ability to modify other roles (Robert Haas)
</para>
<para>
Previously roles with <literal>CREATEROLE</literal> privileges could
change many aspects of any non-superuser role. Such changes,
including adding members, now require the role requesting
the change to have <literal>ADMIN OPTION</literal> permission.
For example, they can now change the <literal>CREATEDB</literal>,
<literal>REPLICATION</literal>, and <literal>BYPASSRLS</literal>
properties only if they also have those permissions.
</para>
</listitem>
<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2023-01-26 [37e267335] Don't install postmaster symlink anymore
-->
<listitem>
<para>
Remove symbolic links for the <application>postmaster</application>
binary (Peter Eisentraut)
</para>
</listitem>
</itemizedlist>
</sect2>
<sect2 id="release-16-changes">
<title>Changes</title>
<para>
Below you will find a detailed account of the changes between
<productname>PostgreSQL</productname> 16 and the previous major
release.
</para>
<sect3 id="release-16-server">
<title>Server</title>
<sect4 id="release-16-optimizer">
<title>Optimizer</title>
<itemizedlist>
<!--
Author: David Rowley <drowley@postgresql.org>
2022-08-02 [b59242209] Relax overly strict rules in select_outer_pathkeys_for_m
Author: David Rowley <drowley@postgresql.org>
2023-01-11 [3c6fc5820] Have the planner consider Incremental Sort for DISTINCT
-->
<listitem>
<para>
Allow incremental sorts in more cases, including
<literal>DISTINCT</literal> (David Rowley)
</para>
</listitem>
<!--
Author: David Rowley <drowley@postgresql.org>
2022-08-02 [1349d2790] Improve performance of ORDER BY / DISTINCT aggregates
Author: David Rowley <drowley@postgresql.org>
2022-12-20 [3226f4728] Add enable_presorted_aggregate GUC
Author: David Rowley <drowley@postgresql.org>
2023-01-17 [da5800d5f] Don't presort ORDER BY/DISTINCT Aggrefs with volatile fu
-->
<listitem>
<para>
Add the ability for aggregates having <literal>ORDER BY</literal>
or <literal>DISTINCT</literal> to use pre-sorted data (David
Rowley)
</para>
<para>
The new server variable <link
linkend="guc-enable-presorted-aggregate"><varname>enable_presorted_aggregate</varname></link>
can be used to disable this.
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-03-16 [9bfd2822b] Enable use of Memoize atop an Append that came from UNIO
-->
<listitem>
<para>
Allow memoize atop a <literal>UNION ALL</literal> (Richard Guo)
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-04-05 [16dc2703c] Support "Right Anti Join" plan shapes.
-->
<listitem>
<para>
Allow anti-joins to be performed with the non-nullable input as
the inner relation (Richard Guo)
</para>
</listitem>
<!--
Author: Thomas Munro <tmunro@postgresql.org>
2023-03-31 [11c2d6fdf] Parallel Hash Full Join.
-->
<listitem>
<para>
Allow parallelization of <link
linkend="queries-join"><literal>FULL</literal></link> and internal
right <literal>OUTER</literal> hash joins (Melanie Plageman,
Thomas Munro)
</para>
</listitem>
<!--
Author: Alexander Korotkov <akorotkov@postgresql.org>
2023-01-08 [cd9479af2] Improve GIN cost estimation
-->
<listitem>
<para>
Improve the accuracy of <link
linkend="gin"><literal>GIN</literal></link> index access optimizer
costs (Ronan Dunklau)
</para>
</listitem>
</itemizedlist>
</sect4>
<sect4 id="release-16-performance">
<title>General Performance</title>
<itemizedlist>
<!--
Author: Andres Freund <andres@anarazel.de>
2023-04-06 [00d1e02be] hio: Use ExtendBufferedRelBy() to extend tables more eff
Author: Andres Freund <andres@anarazel.de>
2023-04-06 [26158b852] Use ExtendBufferedRelTo() in XLogReadBufferExtended()
-->
<listitem>
<para>
Allow more efficient addition of heap and index pages (Andres
Freund)
</para>
</listitem>
<!--
Author: Peter Geoghegan <pg@bowt.ie>
2022-09-08 [d977ffd92] Instrument freezing in autovacuum log reports.
Author: Peter Geoghegan <pg@bowt.ie>
2022-11-15 [9e5405993] Deduplicate freeze plans in freeze WAL records.
Author: Peter Geoghegan <pg@bowt.ie>
2022-12-28 [1de58df4f] Add page-level freezing to VACUUM.
-->
<listitem>
<para>
During non-freeze operations, perform page <link
linkend="vacuum-for-wraparound">freezing</link> where appropriate
(Peter Geoghegan)
</para>
<para>
This makes full-table freeze vacuums less necessary.
</para>
</listitem>
<!--
Author: David Rowley <drowley@postgresql.org>
2022-12-23 [ed1a88dda] Allow window functions to adjust their frameOptions
-->
<listitem>
<para>
Allow window functions to use the faster <link
linkend="syntax-window-functions"><literal>ROWS</literal></link>
mode internally when <literal>RANGE</literal> mode is active but
unnecessary (David Rowley)
</para>
</listitem>
<!--
Author: David Rowley <drowley@postgresql.org>
2023-01-27 [456fa635a] Teach planner about more monotonic window functions
-->
<listitem>
<para>
Allow optimization of always-increasing window functions <link
linkend="functions-window-table"><function>ntile()</function></link>,
<function>cume_dist()</function> and
<function>percent_rank()</function> (David Rowley)
</para>
</listitem>
<!--
Author: David Rowley <drowley@postgresql.org>
2023-01-23 [16fd03e95] Allow parallel aggregate on string_agg and array_agg
-->
<listitem>
<para>
Allow aggregate functions <link
linkend="functions-aggregate-table"><function>string_agg()</function></link>
and <function>array_agg()</function> to be parallelized (David
Rowley)
</para>
</listitem>
<!--
Author: David Rowley <drowley@postgresql.org>
2022-08-02 [3592e0ff9] Have ExecFindPartition cache the last found partition
-->
<listitem>
<para>
Improve performance by caching <link
linkend="ddl-partitioning-overview"><literal>RANGE</literal></link>
and <literal>LIST</literal> partition lookups (Amit Langote,
Hou Zhijie, David Rowley)
</para>
</listitem>
<!--
Author: David Rowley <drowley@postgresql.org>
2023-04-07 [1cbbee033] Add VACUUM/ANALYZE BUFFER_USAGE_LIMIT option
Author: David Rowley <drowley@postgresql.org>
2023-04-07 [ae78cae3b] Add - -buffer-usage-limit option to vacuumdb
Author: Masahiko Sawada <msawada@postgresql.org>
2023-04-28 [b72f564d8] Add unit to vacuum_buffer_usage_limit value in postgresq
-->
<listitem>
<para>
Allow control of the shared buffer usage by vacuum and analyze
(Melanie Plageman)
</para>
<para>
The <link
linkend="sql-vacuum"><command>VACUUM</command></link>/<link
linkend="sql-analyze"><command>ANALYZE</command></link>
option is <literal>BUFFER_USAGE_LIMIT</literal>, and the <link
linkend="app-vacuumdb"><application>vacuumdb</application></link>
option is <option>--buffer-usage-limit</option>.
The default value is set by server variable <link
linkend="guc-vacuum-buffer-usage-limit"><varname>vacuum_buffer_usage_limit</varname></link>,
which also controls autovacuum.
</para>
</listitem>
<!--
Author: Thomas Munro <tmunro@postgresql.org>
2022-07-20 [9430fb407] Add wal_sync_method=fdatasync for Windows.
-->
<listitem>
<para>
Support <link
linkend="guc-wal-sync-method"><literal>wal_sync_method=fdatasync</literal></link>
on <systemitem class="osname">Windows</systemitem> (Thomas Munro)
</para>
</listitem>
<!--
Author: Tomas Vondra <tomas.vondra@postgresql.org>
2023-03-20 [19d8e2308] Ignore BRIN indexes when checking for HOT updates
-->
<listitem>
<para>
Allow <link linkend="storage-hot"><acronym>HOT</acronym></link>
updates if only <literal>BRIN</literal>-indexed columns are updated
(Matthias van de Meent, Josef Simanek, Tomas Vondra)
</para>
</listitem>
<!--
Author: David Rowley <drowley@postgresql.org>
2023-02-20 [2cb82e2ac] Speedup and increase usability of set proc title functio
-->
<listitem>
<para>
Improve the speed of updating the <link
linkend="guc-update-process-title">process title</link> (David
Rowley)
</para>
</listitem>
<!--
Author: John Naylor <john.naylor@postgresql.org>
2022-08-11 [37a6e5df3] Optimize xid/subxid searches in XidInMVCCSnapshot().
Author: John Naylor <john.naylor@postgresql.org>
2022-08-26 [121d2d3d7] Use SSE2 in is_valid_ascii() where available.
Author: John Naylor <john.naylor@postgresql.org>
2022-08-10 [b6ef16756] Introduce optimized routine for linear searches of array
Author: John Naylor <john.naylor@postgresql.org>
2022-08-26 [e813e0e16] Add optimized functions for linear search within byte ar
-->
<listitem>
<para>
Allow <type>xid</type>/<type>subxid</type> searches and
<acronym>ASCII</acronym> string detection to use vector operations
(Nathan Bossart, John Naylor)
</para>
<para>
<acronym>ASCII</acronym> detection is particularly useful for
<link linkend="sql-copy"><command>COPY FROM</command></link>.
Vector operations are also used for some C array searches.
</para>
</listitem>
<!--
Author: David Rowley <drowley@postgresql.org>
2022-08-29 [c6e0fe1f2] Improve performance of and reduce overheads of memory ma
-->
<listitem>
<para>
Reduce overhead of memory allocations (Andres Freund, David Rowley)
</para>
</listitem>
</itemizedlist>
</sect4>
<sect4 id="release-16-monitoring">
<title>Monitoring</title>
<itemizedlist>
<!--
Author: Andres Freund <andres@anarazel.de>
2023-02-11 [a9c70b46d] Add pg_stat_io view, providing more detailed IO statisti
Author: Andres Freund <andres@anarazel.de>
2023-03-30 [8aaa04b32] Track shared buffer hits in pg_stat_io
Author: Andres Freund <andres@anarazel.de>
2023-04-07 [ac8d53dae] Track IO times in pg_stat_io
Author: Michael Paquier <michael@paquier.xyz>
2023-04-21 [0ecb87e1f] Remove io prefix from pg_stat_io columns
Author: Andres Freund <andres@anarazel.de>
2023-05-17 [093e5c57d] Add writeback to pg_stat_io
-->
<listitem>
<para>
Add system view <link
linkend="monitoring-pg-stat-io-view"><structname>pg_stat_io</structname></link>
view to track <acronym>I/O</acronym> statistics (Melanie Plageman)
</para>
</listitem>
<!--
Author: Andres Freund <andres@anarazel.de>
2022-10-14 [c03747183] pgstat: Track time of the last scan of a relation
-->
<listitem>
<para>
Record statistics on the last sequential and index scans on tables
(Dave Page)
</para>
<para>
This information appears in <link
linkend="pg-stat-all-tables-view"><structname>pg_stat_*_tables</structname></link>
and <link
linkend="monitoring-pg-stat-all-indexes-view"><structname>pg_stat_*_indexes</structname></link>.
</para>
</listitem>
<!--
Author: Peter Geoghegan <pg@bowt.ie>
2023-03-23 [ae4fdde13] Count updates that move row to a new page.
-->
<listitem>
<para>
Record statistics on the occurrence of updated rows moving to
new pages (Corey Huinker)
</para>
<para>
The <literal>pg_stat_*_tables</literal> column is <link
linkend="monitoring-pg-stat-all-tables-view"><structfield>n_tup_newpage_upd</structfield></link>.
</para>
</listitem>
<!--
Author: Amit Kapila <akapila@postgresql.org>
2023-01-10 [f74573969] Fix the display of lock information for specktoken.
-->
<listitem>
<para>
Add speculative lock information to the <link
linkend="view-pg-locks"><structname>pg_locks</structname></link>
system view (Masahiko Sawada, Noriyoshi Shinoda)
</para>
<para>
The transaction id is displayed in the
<structfield>transactionid</structfield> column and
the speculative insertion token is displayed in the
<structfield>objid</structfield> column.
</para>
</listitem>
<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2022-07-05 [84ad713cf] Add result_types column to pg_prepared_statements view
Author: Peter Eisentraut <peter@eisentraut.org>
2022-07-05 [6ffff0fd2] Fix pg_prepared_statements.result_types for DML statemen
-->
<listitem>
<para>
Add the display of prepared statement result types to the <link
linkend="view-pg-prepared-statements"><structname>pg_prepared_statements</structname></link>
view (Dagfinn Ilmari Mannsåker)
</para>
</listitem>
<!--
Author: Andres Freund <andres@anarazel.de>
2022-10-06 [e0b014295] Create subscription stats entry at CREATE SUBSCRIPTION t
-->
<listitem>
<para>
Create subscription statistics
entries at subscription creation time so <link
linkend="pg-stat-database-view"><structfield>stats_reset</structfield></link>
is accurate (Andres Freund)
</para>
<para>
Previously entries were created only when the first statistics
were reported.
</para>
</listitem>
<!--
Author: Andres Freund <andres@anarazel.de>
2023-04-07 [704261ecc] Improve IO accounting for temp relation writes
-->
<listitem>
<para>
Correct the <acronym>I/O</acronym>
accounting for temp relation writes shown in <link
linkend="pg-stat-database-view"><structname>pg_stat_database</structname></link>
(Melanie Plageman)
</para>
</listitem>
<!--
Author: Robert Haas <rhaas@postgresql.org>
2022-12-19 [10ea0f924] Expose some information about backend subxact status.
-->
<listitem>
<para>
Add function <link
linkend="monitoring-stats-backend-funcs-table"><function>pg_stat_get_backend_subxact()</function></link>
to report on a session's subtransaction cache (Dilip Kumar)
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2022-09-29 [d7e39d72c] Use actual backend IDs in pg_stat_get_backend_idset() an
-->
<listitem>
<para>
Have <link
linkend="monitoring-stats-backend-funcs-table"><function>pg_stat_get_backend_idset()</function></link>,
<function>pg_stat_get_backend_activity()</function>, and related
functions use the unchanging backend id (Nathan Bossart)
</para>
<para>
Previously the index values might change during the lifetime of
the session.
</para>
</listitem>
<!--
Author: Andres Freund <andres@anarazel.de>
2022-08-22 [0c679464a] Add BackendType for standalone backends
-->
<listitem>
<para>
Report stand-alone backends with a special backend type (Melanie
Plageman)
</para>
</listitem>
<!--
Author: Andres Freund <andres@anarazel.de>
2022-11-21 [92daeca45] Add wait event for pg_usleep() in perform_spin_delay()
-->
<listitem>
<para>
Add wait event <link
linkend="wait-event-timeout-table"><literal>SpinDelay</literal></link>
to report spinlock sleep delays (Andres Freund)
</para>
</listitem>
<!--
Author: Thomas Munro <tmunro@postgresql.org>
2022-07-14 [7bae3bbf6] Create a distinct wait event for POSIX DSM allocation.
-->
<listitem>
<para>
Create new wait event <link
linkend="wait-event-io-table"><literal>DSMAllocate</literal></link>
to indicate waiting for dynamic shared memory allocation (Thomas
Munro)
</para>
<para>
Previously this type of wait was reported as
<literal>DSMFillZeroWrite</literal>, which was also used by
<function>mmap()</function> allocations.
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2022-11-24 [af205152e] Add the database name to the ps display of logical WAL s
-->
<listitem>
<para>
Add the database name to the <link
linkend="guc-update-process-title">process title</link> of logical
<acronym>WAL</acronym> senders (Tatsuhiro Nakamori)
</para>
<para>
Physical <acronym>WAL</acronym> senders do not display a database
name.
</para>
</listitem>
<!--
Author: Fujii Masao <fujii@postgresql.org>
2022-07-07 [62c46eee2] Add checkpoint and REDO LSN to log_checkpoints message.
-->
<listitem>
<para>
Add checkpoint and <literal>REDO LSN</literal> information to <link
linkend="guc-log-checkpoints"><varname>log_checkpoints</varname></link>
messages (Bharath Rupireddy, Kyotaro Horiguchi)
</para>
</listitem>
<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2022-07-15 [3a0e38504] Log details for client certificate failures
-->
<listitem>
<para>
Provide additional details during client certificate failures
(Jacob Champion)
</para>
</listitem>
</itemizedlist>
</sect4>
<sect4 id="release-16-privileges">
<title>Privileges</title>
<itemizedlist>
<!--
Author: Robert Haas <rhaas@postgresql.org>
2023-03-30 [c3afe8cf5] Add new predefined role pg_create_subscription.
-->
<listitem>
<para>
Add predefined role <link
linkend="predefined-roles"><literal>pg_create_subscription</literal></link>
with permission to create subscriptions (Robert Haas)
</para>
</listitem>
<!--
Author: Robert Haas <rhaas@postgresql.org>
2023-03-30 [c3afe8cf5] Add new predefined role pg_create_subscription.
Author: Amit Kapila <akapila@postgresql.org>
2023-04-20 [c1cc4e688] Restart the apply worker if the 'password_required' opti
Author: Amit Kapila <akapila@postgresql.org>
2023-04-24 [19e65dff3] Display 'password_required' option for \dRs+ command.
-->
<listitem>
<para>
Allow subscriptions to not require passwords (Robert Haas)
</para>
<para>
This is accomplished with the option <link
linkend="sql-createsubscription"><literal>password_required=false</literal></link>.
</para>
</listitem>
<!--
Author: Jeff Davis <jdavis@postgresql.org>
2023-01-13 [c44f6334c] Simplify permissions for LOCK TABLE.
-->
<listitem>
<para>
Simplify permissions for <link linkend="sql-lock"><command>LOCK
TABLE</command></link> (Jeff Davis)
</para>
<para>
Previously a user's ability to perform <command>LOCK
TABLE</command> at various lock levels was limited to the
lock levels required by the commands they had permission
to execute on the table. For example, someone with <link
linkend="sql-update"><command>UPDATE</command></link>
permission could perform all lock levels except <literal>ACCESS
SHARE</literal>, even though it was a lesser lock level. Now users
can issue lesser lock levels if they already have permission for
greater lock levels.
</para>
</listitem>
<!--
Author: Robert Haas <rhaas@postgresql.org>
2022-08-22 [ce6b672e4] Make role grant system more consistent with other privil
-->
<listitem>
<para>
Allow <link linkend="sql-altergroup"><literal>ALTER GROUP group_name
ADD USER user_name</literal></link> to be performed with <literal>ADMIN
OPTION</literal> (Robert Haas)
</para>
<para>
Previously <literal>CREATEROLE</literal> permission was required.
</para>
</listitem>
<!--
Author: Robert Haas <rhaas@postgresql.org>
2022-08-25 [e3ce2de09] Allow grant-level control of role inheritance behavior.
-->
<listitem>
<para>
Allow <link linkend="sql-grant"><command>GRANT</command></link>
to use <literal>WITH ADMIN TRUE</literal>/<literal>FALSE</literal>
syntax (Robert Haas)
</para>
<para>
Previously only the <literal>WITH ADMIN OPTION</literal> syntax
was supported.
</para>
</listitem>
<!--
Author: Robert Haas <rhaas@postgresql.org>
2023-01-10 [e5b8a4c09] Add new GUC createrole_self_grant.
Author: Daniel Gustafsson <dgustafsson@postgresql.org>
2023-02-22 [e00bc6c92] doc: Add default value of createrole_self_grant
-->
<listitem>
<para>
Allow roles that create other roles to automatically
inherit the new role's rights or the ability to <link
linkend="sql-set-role"><command>SET ROLE</command></link> to the
new role (Robert Haas, Shi Yu)
</para>
<para>
This is controlled by server variable <link
linkend="guc-createrole-self-grant"><varname>createrole_self_grant</varname></link>.
</para>
</listitem>
<!--
Author: Robert Haas <rhaas@postgresql.org>
2022-09-19 [48a257d44] Make ALTER DEFAULT PRIVILEGES require privileges, not me
-->
<listitem>
<para>
Prevent users from changing the default privileges of non-inherited
roles (Robert Haas)
</para>
<para>
This is now only allowed for inherited roles.
</para>
</listitem>
<!--
Author: Robert Haas <rhaas@postgresql.org>
2022-08-22 [ce6b672e4] Make role grant system more consistent with other privil
-->
<listitem>
<para>
When granting role membership, require the granted-by role to be
a role that has appropriate permissions (Robert Haas)
</para>
<para>
This is a requirement even when a non-bootstrap superuser is
granting role membership.
</para>
</listitem>
<!--
Author: Robert Haas <rhaas@postgresql.org>
2022-08-22 [ce6b672e4] Make role grant system more consistent with other privil
-->
<listitem>
<para>
Allow non-superusers to grant permissions using a granted-by user
that is not the current user (Robert Haas)
</para>
<para>
The current user still must have sufficient permissions given by
the specified granted-by user.
</para>
</listitem>
<!--
Author: Robert Haas <rhaas@postgresql.org>
2022-11-18 [3d14e171e] Add a SET option to the GRANT command.
-->
<listitem>
<para>
Add <link linkend="sql-grant"><command>GRANT</command></link> to
control permission to use <link linkend="sql-set-role"><command>SET
ROLE</command></link> (Robert Haas)
</para>
<para>
This is controlled by a new <literal>GRANT ... SET</literal>
option.
</para>
</listitem>
<!--
Author: Robert Haas <rhaas@postgresql.org>
2022-08-22 [ce6b672e4] Make role grant system more consistent with other privil
-->
<listitem>
<para>
Add dependency tracking to roles which have granted privileges
(Robert Haas)
</para>
<para>
For example, removing <literal>ADMIN OPTION</literal> will fail if
there are privileges using that option; <literal>CASCADE</literal>
must be used to revoke dependent permissions.
</para>
</listitem>
<!--
Author: Robert Haas <rhaas@postgresql.org>
2022-08-18 [6566133c5] Ensure that pg_auth_members.grantor is always valid.
-->
<listitem>
<para>
Add dependency tracking of grantors for <link
linkend="sql-grant"><command>GRANT</command></link> records
(Robert Haas)
</para>
<para>
This guarantees that <link
linkend="catalog-pg-auth-members"><structname>pg_auth_members</structname></link>.<structfield>grantor</structfield>
values are always valid.
</para>
</listitem>
<!--
Author: Robert Haas <rhaas@postgresql.org>
2022-08-22 [ce6b672e4] Make role grant system more consistent with other privil
Author: Robert Haas <rhaas@postgresql.org>
2022-08-31 [0101f770a] Fix a bug in roles_is_member_of.
-->
<listitem>
<para>
Allow multiple role membership records (Robert Haas)
</para>
<para>
Previously a new membership grant would remove a previous matching
membership grant, even if other aspects of the grant did not match.
</para>
</listitem>
<!--
Author: Robert Haas <rhaas@postgresql.org>
2022-07-26 [e530be2c5] Do not allow removal of superuser privileges from bootst
-->
<listitem>
<para>
Prevent removal of superuser privileges for the bootstrap user
(Robert Haas)
</para>
<para>
Restoring such users could lead to errors.
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2022-07-03 [b762bbde3] Allow makeaclitem() to accept multiple privilege names.
-->
<listitem>
<para>
Allow <link
linkend="functions-aclitem-fn-table"><function>makeaclitem()</function></link>
to accept multiple privilege names (Robins Tharakan)
</para>
<para>
Previously only a single privilege name, like <link
linkend="sql-select"><command>SELECT</command></link>, was
accepted.
</para>
</listitem>
</itemizedlist>
</sect4>
<sect4 id="release-16-server-config">
<title>Server Configuration</title>
<itemizedlist>
<!--
Author: Stephen Frost <sfrost@snowman.net>
2023-04-13 [6633cfb21] De-Revert "Add support for Kerberos credential delegatio
Author: Bruce Momjian <bruce@momjian.us>
2023-05-20 [9c0a0e2ed] rename "gss_accept_deleg" to "gss_accept_delegation".
Author: Nathan Bossart <nathan@postgresql.org>
2023-05-20 [f4001a553] Fix remaining references to gss_accept_deleg.
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-05-21 [a2eb99a01] Expand some more uses of "deleg" to "delegation" or "del
-->
<listitem>
<para>
Add support for <productname>Kerberos</productname> credential
delegation (Stephen Frost)
</para>
<para>
This is enabled with server variable <link
linkend="guc-gss-accept-delegation"><varname>gss_accept_delegation</varname></link>
and <application>libpq</application> connection parameter <link
linkend="libpq-connect-gssdelegation"><literal>gssdelegation</literal></link>.
</para>
</listitem>
<!--
Author: Daniel Gustafsson <dgustafsson@postgresql.org>
2023-03-27 [b57774300] Make SCRAM iteration count configurable
-->
<listitem>
<para>
Allow the <acronym>SCRAM</acronym> iteration
count to be set with server variable <link
linkend="guc-scram-iterations"><varname>scram_iterations</varname></link>
(Daniel Gustafsson)
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2022-10-14 [3057465ac] Replace the sorted array of GUC variables with a hash ta
Author: Tom Lane <tgl@sss.pgh.pa.us>
2022-10-14 [f13b2088f] Add auxiliary lists to GUC data structures for better pe
-->
<listitem>
<para>
Improve performance of server variable management (Tom Lane)
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2022-09-27 [385366426] Introduce GUC_NO_RESET flag.
-->
<listitem>
<para>
Tighten restrictions on which server variables can be reset
(Masahiko Sawada)
</para>
<para>
Previously, while certain variables, like <link
linkend="guc-default-transaction-isolation"><varname>transaction_isolation</varname></link>,
were not affected by <link linkend="sql-reset"><command>RESET
ALL</command></link>, they could be individually reset in
inappropriate situations.
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2022-08-09 [0b039e3a8] Fix some inconsistencies with GUC categories
-->
<listitem>
<para>
Move various <link
linkend="config-setting-configuration-file"><filename>postgresql.conf</filename></link>
items into new categories (Shinya Kato)
</para>
<para>
This also affects the categories displayed in the <link
linkend="view-pg-settings"><structname>pg_settings</structname></link>
view.
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2022-11-25 [d13b68411] Introduce variables for initial and max nesting depth on
-->
<listitem>
<para>
Prevent configuration file recursion beyond 10 levels (Julien
Rouhaud)
</para>
</listitem>
<!--
Author: Daniel Gustafsson <dgustafsson@postgresql.org>
2023-04-07 [7d71d3dd0] Refresh cost-based delay params more frequently in autov
Author: Daniel Gustafsson <dgustafsson@postgresql.org>
2023-04-20 [a9781ae11] Fix autovacuum cost debug logging
-->
<listitem>
<para>
Allow <link linkend="autovacuum">autovacuum</link> to more
frequently honor changes to delay settings (Melanie Plageman)
</para>
<para>
Rather than honor changes only at the start of each relation,
honor them at the start of each block.
</para>
</listitem>
<!--
Author: Fujii Masao <fujii@postgresql.org>
2022-07-26 [756e221db] Reduce overhead of renaming archive status files.
Author: Fujii Masao <fujii@postgresql.org>
2022-07-26 [3cabe45a8] doc: Add note about re-archiving of same WAL files in do
-->
<listitem>
<para>
Remove restrictions that archive files be durably renamed
(Nathan Bossart)
</para>
<para>
The <link
linkend="guc-archive-command"><varname>archive_command</varname></link>
command is now more likely to be called with already-archived
files after a crash.
</para>
</listitem>
<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2022-11-15 [d627ce3b7] Disallow setting archive_library and archive_command at
-->
<listitem>
<para>
Prevent <link
linkend="guc-archive-library"><varname>archive_library</varname></link>
and <link
linkend="guc-archive-command"><varname>archive_command</varname></link>
from being set at the same time (Nathan Bossart)
</para>
<para>
Previously <varname>archive_library</varname> would override
<varname>archive_command</varname>.
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2022-11-21 [51b5834cd] Provide options for postmaster to kill child processes w
-->
<listitem>
<para>
Allow the postmaster to terminate children with an abort signal
(Tom Lane)
</para>
<para>
This allows collection of a core dump for a
stuck child process. This is controlled by <link
linkend="guc-send-abort-for-crash"><varname>send_abort_for_crash</varname></link>
and <link
linkend="guc-send-abort-for-kill"><varname>send_abort_for_kill</varname></link>.
The postmaster's <option>-T</option> switch is now the same as
setting <varname>send_abort_for_crash</varname>.
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2022-11-21 [51b5834cd] Provide options for postmaster to kill child processes w
-->
<listitem>
<para>
Remove the non-functional postmaster <option>-n</option> option
(Tom Lane)
</para>
</listitem>
<!--
Author: Robert Haas <rhaas@postgresql.org>
2023-01-20 [6e2775e4d] Add new GUC reserved_connections.
-->
<listitem>
<para>
Allow the server to reserve backend slots for roles with <link
linkend="predefined-roles"><literal>pg_use_reserved_connections</literal></link>
membership (Nathan Bossart)
</para>
<para>
The number of reserved slots is set by server variable <link
linkend="guc-reserved-connections"><varname>reserved_connections</varname></link>.
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2022-09-17 [fdd8937c0] Fix huge_pages on Windows
-->
<listitem>
<para>
Allow <link linkend="guc-huge-pages">huge pages</link> to
work on newer versions of <systemitem class="osname">Windows
10</systemitem> (Thomas Munro)
</para>
<para>
This adds the special handling required to enable huge pages
on newer versions of <systemitem class="osname">Windows
10</systemitem>.
</para>
</listitem>
<!--
Author: Thomas Munro <tmunro@postgresql.org>
2023-04-08 [d4e71df6d] Add io_direct setting (developer-only).
Author: Thomas Munro <tmunro@postgresql.org>
2023-05-15 [319bae9a8] Rename io_direct to debug_io_direct.
-->
<listitem>
<para>
Add <link
linkend="guc-debug-io-direct"><varname>debug_io_direct</varname></link>
setting for developer usage (Thomas Munro, Andres Freund,
Bharath Rupireddy)
</para>
<para>
While primarily for developers, <link
linkend="guc-wal-sync-method"><literal>wal_sync_method=open_sync</literal></link>/<literal>open_datasync</literal>
has been modified to not use direct <acronym>I/O</acronym> with
<literal>wal_level=minimal</literal>; this is now enabled with
<literal>debug_io_direct=wal</literal>.
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2022-12-20 [cca186348] Add pg_dissect_walfile_name()
Author: Michael Paquier <michael@paquier.xyz>
2022-12-23 [13e0d7a60] Rename pg_dissect_walfile_name() to pg_split_walfile_nam
-->
<listitem>
<para>
Add function <link
linkend="functions-admin-backup-table"><function>pg_split_walfile_name()</function></link>
to report the segment and timeline values of <acronym>WAL</acronym>
file names (Bharath Rupireddy)
</para>
</listitem>
</itemizedlist>
</sect4>
<sect4 id="release-16-pg-hba">
<title><link linkend="auth-pg-hba-conf">pg_hba.conf</link></title>
<itemizedlist>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2022-10-24 [8fea86830] Add support for regexps on database and user entries in
-->
<listitem>
<para>
Add support for regular expression matching on database and role
entries in <filename>pg_hba.conf</filename> (Bertrand Drouvot)
</para>
<para>
Regular expression patterns are prefixed with a slash. Database
and role names that begin with slashes need to be double-quoted
if referenced in <filename>pg_hba.conf</filename>.
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2023-01-20 [efb6f4a4f] Support the same patterns for pg-user in pg_ident.conf a
-->
<listitem>
<para>
Improve user-column handling of <link
linkend="runtime-config-file-locations"><filename>pg_ident.conf</filename></link>
to match <filename>pg_hba.conf</filename> (Jelte Fennema)
</para>
<para>
Specifically, add support for <literal>all</literal>, role
membership with <literal>+</literal>, and regular expressions
with a leading slash. Any user name that matches these patterns
must be double-quoted.
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2022-11-24 [a54b658ce] Add support for file inclusions in HBA and ident configu
-->
<listitem>
<para>
Allow include files in <filename>pg_hba.conf</filename> and
<filename>pg_ident.conf</filename> (Julien Rouhaud)
</para>
<para>
These are controlled by <literal>include</literal>,
<literal>include_if_exists</literal>, and
<literal>include_dir</literal>. System views <link
linkend="view-pg-hba-file-rules"><structname>pg_hba_file_rules</structname></link>
and <link
linkend="view-pg-ident-file-mappings"><structname>pg_ident_file_mappings</structname></link>
now display the file name.
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-07-27 [de3f0e3fe] Eliminate fixed token-length limit in hba.c.
-->
<listitem>
<para>
Allow <filename>pg_hba.conf</filename> tokens to be of unlimited
length (Tom Lane)
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2022-10-26 [c591300a8] Add rule_number to pg_hba_file_rules and map_number to p
-->
<listitem>
<para>
Add rule and map numbers to the system view <link
linkend="view-pg-hba-file-rules"><structname>pg_hba_file_rules</structname></link>
(Julien Rouhaud)
</para>
</listitem>
</itemizedlist>
</sect4>
<sect4 id="release-16-localization">
<title><link linkend="charset">Localization</link></title>
<itemizedlist>
<!--
Author: Jeff Davis <jdavis@postgresql.org>
2023-03-10 [c45dc7ffb] initdb: derive encoding from locale for ICU; similar to
-->
<listitem>
<para>
Determine the default encoding from the locale when using
<acronym>ICU</acronym> (Jeff Davis)
</para>
<para>
Previously the default was always <literal>UTF-8</literal>.
</para>
</listitem>
<!--
Author: Jeff Davis <jdavis@postgresql.org>
Date: Fri Jun 16 10:27:32 2023 -0700
-->
<listitem>
<para>
Have <link linkend="sql-createdatabase"><command>CREATE
DATABASE</command></link> and <link
linkend="sql-createcollation"><command>CREATE
COLLATION</command></link>'s <literal>LOCALE</literal> options, and
<link linkend="app-initdb"><application>initdb</application></link>
and <link
linkend="app-createdb"><application>createdb</application></link>
<option>--locale</option> options, control
non-<application>libc</application> collation providers (Jeff
Davis)
</para>
<para>
Previously they only controlled <application>libc</application>
providers.
</para>
</listitem>
<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2023-03-10 [0d21d4b9b] Add standard collation UNICODE
-->
<listitem>
<para>
Add predefined collations <literal>unicode</literal> and
<literal>ucs_basic</literal> (Peter Eisentraut)
</para>
<para>
This only works if <acronym>ICU</acronym> support is enabled.
</para>
</listitem>
<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2023-03-08 [30a53b792] Allow tailoring of ICU locales with custom rules
-->
<listitem>
<para>
Allow custom <acronym>ICU</acronym> collation rules to be created
(Peter Eisentraut)
</para>
<para>
This is done using <link
linkend="sql-createcollation"><command>CREATE
COLLATION</command></link>'s new <literal>RULES</literal>
clause, as well as new options for <link
linkend="sql-createdatabase"><command>CREATE
DATABASE</command></link>, <link
linkend="app-createdb"><application>createdb</application></link>,
and <link
linkend="app-initdb"><application>initdb</application></link>.
</para>
</listitem>
<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2023-01-03 [bf03cfd16] Windows support in pg_import_system_collations
-->
<listitem>
<para>
Allow <systemitem class="osname">Windows</systemitem> to import
system locales automatically (Juan José Santamaría Flecha)
</para>
<para>
Previously, only <acronym>ICU</acronym> locales could be imported
on <systemitem class="osname">Windows</systemitem>.
</para>
</listitem>
</itemizedlist>
</sect4>
</sect3>
<sect3 id="release-16-logical">
<title><link linkend="logical-replication">Logical Replication</link></title>
<itemizedlist>
<!--
Author: Andres Freund <andres@anarazel.de>
2023-04-08 [0fdab27ad] Allow logical decoding on standbys
Author: Andres Freund <andres@anarazel.de>
2023-04-07 [be87200ef] Support invalidating replication slots due to horizon an
Author: Andres Freund <andres@anarazel.de>
2023-04-08 [26669757b] Handle logical slot conflicts on standby
-->
<listitem>
<para>
Allow <link linkend="logicaldecoding">logical decoding</link>
on standbys (Bertrand Drouvot, Andres Freund, Amit Khandekar)
</para>
<para>
Snapshot <acronym>WAL</acronym> records are
required for logical slot creation but cannot be
created on standbys. To avoid delays, the new function <link
linkend="functions-snapshot-synchronization-table"><function>pg_log_standby_snapshot()</function></link>
allows creation of such records.
</para>
</listitem>
<!--
Author: Amit Kapila <akapila@postgresql.org>
2022-12-26 [5de94a041] Add 'logical_decoding_mode' GUC.
Author: Amit Kapila <akapila@postgresql.org>
2023-01-30 [1e8b61735] Rename GUC logical_decoding_mode to logical_replication_
Author: Amit Kapila <akapila@postgresql.org>
2023-02-02 [9f2213a7c] Allow the logical_replication_mode to be used on the sub
-->
<listitem>
<para>
Add server variable to control how logical decoding publishers
transfer changes and how subscribers apply them (Shi Yu)
</para>
<para>
The variable is <link
linkend="guc-debug-logical-replication-streaming"><varname>debug_logical_replication_streaming</varname></link>.
</para>
</listitem>
<!--
Author: Amit Kapila <akapila@postgresql.org>
2023-03-23 [ecb696527] Allow logical replication to copy tables in binary forma
-->
<listitem>
<para>
Allow logical replication initial table synchronization to copy
rows in binary format (Melih Mutlu)
</para>
<para>
This is only possible for subscriptions marked as binary.
</para>
</listitem>
<!--
Author: Amit Kapila <akapila@postgresql.org>
2023-01-09 [216a78482] Perform apply of large transactions by parallel workers.
Author: Amit Kapila <akapila@postgresql.org>
2023-01-10 [cd06ccd78] Document the newly added wait events added by commit 216
Author: Amit Kapila <akapila@postgresql.org>
2023-02-16 [fce003cfd] Add a new wait state and use it when sending data in the
-->
<listitem>
<para>
Allow parallel application of logical replication (Hou Zhijie,
Wang Wei, Amit Kapila)
</para>
<para>
The <link linkend="sql-createsubscription"><command>CREATE
SUBSCRIPTION</command></link> <option>STREAMING</option>
option now supports <literal>parallel</literal> to enable
application of large transactions by parallel workers. The number
of parallel workers is controlled by the new server variable <link
linkend="guc-max-parallel-apply-workers-per-subscription"><varname>max_parallel_apply_workers_per_subscription</varname></link>.
Wait events <link
linkend="wait-event-activity-table"><literal>LogicalParallelApplyMain</literal></link>,
<literal>LogicalParallelApplyStateChange</literal>, and
<literal>LogicalApplySendData</literal> were also added. Column
<structfield>leader_pid</structfield> was added to system view <link
linkend="monitoring-pg-stat-subscription"><structname>pg_stat_subscription</structname></link>
to track parallel activity.
</para>
</listitem>
<!--
Author: Amit Kapila <akapila@postgresql.org>
2023-03-15 [89e46da5e] Allow the use of indexes other than PK and REPLICA IDENT
-->
<listitem>
<para>
Improve performance for <link
linkend="logical-replication-architecture">logical replication
apply</link> without a primary key (Onder Kalaci, Amit Kapila)
</para>
<para>
Specifically, <literal>REPLICA IDENTITY FULL</literal> can now
use btree indexes rather than sequentially scanning the table to
find matches.
</para>
</listitem>
<!--
Author: Amit Kapila <akapila@postgresql.org>
2022-07-21 [366283961] Allow users to skip logical replication of data having o
Author: Amit Kapila <akapila@postgresql.org>
2022-09-08 [875693019] Raise a warning if there is a possibility of data from m
-->
<listitem>
<para>
Allow logical replication subscribers to process only changes that
have no origin (Vignesh C, Amit Kapila)
</para>
<para>
This can be used to avoid replication loops. This is controlled
by the new <literal>CREATE SUBSCRIPTION ... ORIGIN</literal> option.
</para>
</listitem>
<!--
Author: Robert Haas <rhaas@postgresql.org>
2023-04-04 [1e10d49b6] Perform logical replication actions as the table owner.
Author: Robert Haas <rhaas@postgresql.org>
2023-04-04 [482675987] Add a run_as_owner option to subscriptions.
-->
<listitem>
<para>
Perform logical replication <link
linkend="sql-select"><command>SELECT</command></link> and
<acronym>DML</acronym> actions as the table owner (Robert Haas)
</para>
<para>
This improves security and now requires subscription
owners to be either superusers or to have <link
linkend="sql-set-role"><command>SET ROLE</command></link>
permission on all roles owning tables in the replication set.
The previous behavior of performing all operations as the
subscription owner can be enabled with the subscription <link
linkend="sql-createsubscription"><option>run_as_owner</option></link>
option.
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-01-22 [5a3a95385] Track logrep apply workers' last start times to avoid us
-->
<listitem>
<para>
Have <link
linkend="guc-wal-retrieve-retry-interval"><varname>wal_retrieve_retry_interval</varname></link>
operate on a per-subscription basis (Nathan Bossart)
</para>
<para>
Previously the retry time was applied
globally. This also adds wait events <link
linkend="wait-event-lwlock-table">><literal>LogicalRepLauncherDSA</literal></link>
and <literal>LogicalRepLauncherHash</literal>.
</para>
</listitem>
</itemizedlist>
</sect3>
<sect3 id="release-16-utility">
<title>Utility Commands</title>
<itemizedlist>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-03-24 [3c05284d8] Invent GENERIC_PLAN option for EXPLAIN.
-->
<listitem>
<para>
Add <link linkend="sql-explain"><command>EXPLAIN</command></link>
option <literal>GENERIC_PLAN</literal> to display the generic plan
for a parameterized query (Laurenz Albe)
</para>
</listitem>
<!--
Author: Andrew Dunstan <andrew@dunslane.net>
2023-03-13 [9f8377f7a] Add a DEFAULT option to COPY FROM
-->
<listitem>
<para>
Allow a <link linkend="sql-copy"><command>COPY FROM</command></link>
value to map to a column's <literal>DEFAULT</literal> (Israel
Barth Rubio)
</para>
</listitem>
<!--
Author: Etsuro Fujita <efujita@postgresql.org>
2022-10-13 [97da48246] Allow batch insertion during COPY into a foreign table.
-->
<listitem>
<para>
Allow <link linkend="sql-copy"><command>COPY</command></link>
into foreign tables to add rows in batches (Andrey Lepikhov,
Etsuro Fujita)
</para>
<para>
This is controlled by the <link
linkend="postgres-fdw"><application>postgres_fdw</application></link>
option <link
linkend="postgres-fdw-options-cost-estimation"><option>batch_size</option></link>.
</para>
</listitem>
<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2022-07-13 [784cedda0] Allow specifying STORAGE attribute for a new table
Author: Tom Lane <tgl@sss.pgh.pa.us>
2022-11-10 [b9424d014] Support writing "CREATE/ALTER TABLE ... SET STORAGE DEFA
-->
<listitem>
<para>
Allow the <literal>STORAGE</literal> type to be specified by <link
linkend="sql-createtable"><command>CREATE TABLE</command></link>
(Teodor Sigaev, Aleksander Alekseev)
</para>
<para>
Previously only <link linkend="sql-altertable"><command>ALTER
TABLE</command></link> could control this.
</para>
</listitem>
<!--
Author: Fujii Masao <fujii@postgresql.org>
2022-07-12 [3b00a944a] Support TRUNCATE triggers on foreign tables.
-->
<listitem>
<para>
Allow <link linkend="sql-createtrigger">truncate triggers</link>
on foreign tables (Yugo Nagata)
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2023-03-06 [4211fbd84] Add PROCESS_MAIN to VACUUM
-->
<listitem>
<para>
Allow <link
linkend="sql-vacuum"><command>VACUUM</command></link> and <link
linkend="app-vacuumdb"><application>vacuumdb</application></link>
to only process <link
linkend="storage-toast"><literal>TOAST</literal></link> tables
(Nathan Bossart)
</para>
<para>
This is accomplished by having <link
linkend="sql-vacuum"><command>VACUUM</command></link>
turn off <literal>PROCESS_MAIN</literal> or by <link
linkend="app-vacuumdb"><application>vacuumdb</application></link>
using the <option>--no-process-main</option> option.
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-01-06 [a46a7011b] Add options to control whether VACUUM runs vac_update_da
-->
<listitem>
<para>
Add <link linkend="sql-vacuum"><command>VACUUM</command></link>
options to skip or update all <link
linkend="vacuum-for-wraparound">frozen</link> statistics (Tom Lane,
Nathan Bossart)
</para>
<para>
The options are <literal>SKIP_DATABASE_STATS</literal> and
<literal>ONLY_DATABASE_STATS</literal>.
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2022-07-19 [2cbc3c17a] Rework logic and simplify syntax of REINDEX DATABASE/SYS
Author: Michael Paquier <michael@paquier.xyz>
2022-07-26 [0a5f06b84] Fix a few issues with REINDEX grammar
-->
<listitem>
<para>
Change <link linkend="sql-reindex"><command>REINDEX
DATABASE</command></link> and <link
linkend="sql-reindex"><command>REINDEX SYSTEM</command></link>
to no longer require an argument (Simon Riggs)
</para>
<para>
Previously the database name had to be specified.
</para>
</listitem>
<!--
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
2022-07-21 [624aa2a13] Make the name optional in CREATE STATISTICS.
-->
<listitem>
<para>
Allow <link linkend="sql-createstatistics"><command>CREATE
STATISTICS</command></link> to generate a statistics name if none
is specified (Simon Riggs)
</para>
</listitem>
</itemizedlist>
</sect3>
<sect3 id="release-16-datatypes">
<title>Data Types</title>
<itemizedlist>
<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2022-12-14 [6fcda9aba] Non-decimal integer literals
-->
<listitem>
<para>
Allow non-decimal <link linkend="sql-syntax-bit-strings">integer
literals</link> (Peter Eisentraut)
</para>
<para>
For example, <literal>0x42F</literal>, <literal>0o273</literal>,
and <literal>0b100101</literal>.
</para>
</listitem>
<!--
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
2023-01-23 [6dfacbf72] Add non-decimal integer support to type numeric.
-->
<listitem>
<para>
Allow <link linkend="datatype-numeric"><type>NUMERIC</type></link>
to process hexadecimal, octal, and binary integers of any size
(Dean Rasheed)
</para>
<para>
Previously only unquoted eight-byte integers were supported with
these non-decimal bases.
</para>
</listitem>
<!--
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
2023-02-04 [faff8f8e4] Allow underscores in integer and numeric constants.
-->
<listitem>
<para>
Allow underscores in integer and numeric <link
linkend="sql-syntax-bit-strings">constants</link> (Peter Eisentraut,
Dean Rasheed)
</para>
<para>
This can improve readability for long strings of digits.
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-01-01 [2ceea5adb] Accept "+infinity" in date and timestamp[tz] input.
-->
<listitem>
<para>
Accept the spelling <literal>+infinity</literal> in datetime input
(Vik Fearing)
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-03-09 [bcc704b52] Reject combining "epoch" and "infinity" with other datet
-->
<listitem>
<para>
Prevent the specification of <literal>epoch</literal> and
<literal>infinity</literal> together with other fields in datetime
strings (Joseph Koshakow)
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-03-16 [5b3c59535] Tighten error checks in datetime input, and remove bogus
-->
<listitem>
<para>
Remove undocumented support for date input in the form
<literal>Y<replaceable>year</replaceable>M<replaceable>month</replaceable>D<replaceable>day</replaceable></literal>
(Joseph Koshakow)
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2022-12-09 [1939d2628] Add test scaffolding for soft error reporting from input
Author: Michael Paquier <michael@paquier.xyz>
2023-02-28 [b8da37b3a] Rework pg_input_error_message(), now renamed pg_input_er
-->
<listitem>
<para>
Add functions <link
linkend="functions-info-validity-table"><function>pg_input_is_valid()</function></link>
and <function>pg_input_error_info()</function> to check for type
conversion errors (Tom Lane)
</para>
</listitem>
</itemizedlist>
</sect3>
<sect3 id="release-16-general">
<title>General Queries</title>
<itemizedlist>
<!--
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
2022-07-20 [bcedd8f5f] Make subquery aliases optional in the FROM clause.
-->
<listitem>
<para>
Allow subqueries in the <literal>FROM</literal> clause to omit
aliases (Dean Rasheed)
</para>
</listitem>
<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2023-03-05 [102a5c164] SQL JSON path enhanced numeric literals
-->
<listitem>
<para>
Add support for enhanced numeric literals in
<acronym>SQL/JSON</acronym> paths (Peter Eisentraut)
</para>
<para>
For example, allow hexadecimal, octal, and binary integers and
underscores between digits.
</para>
</listitem>
</itemizedlist>
</sect3>
<sect3 id="release-16-functions">
<title>Functions</title>
<itemizedlist>
<!--
Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
2023-03-29 [7081ac46a] SQL/JSON: add standard JSON constructor functions
-->
<listitem>
<para>
Add <acronym>SQL/JSON</acronym> constructors (Nikita Glukhov,
Teodor Sigaev, Oleg Bartunov, Alexander Korotkov, Amit Langote)
</para>
<para>
The new functions <link
linkend="functions-json-creation-table"><function>JSON_ARRAY()</function></link>,
<link
linkend="functions-aggregate-table"><function>JSON_ARRAYAGG()</function></link>,
<function>JSON_OBJECT()</function>, and
<function>JSON_OBJECTAGG()</function> are part of the
<acronym>SQL</acronym> standard.
</para>
</listitem>
<!--
Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
2023-03-31 [6ee30209a] SQL/JSON: support the IS JSON predicate
-->
<listitem>
<para>
Add <acronym>SQL/JSON</acronym> object checks (Nikita Glukhov,
Teodor Sigaev, Oleg Bartunov, Alexander Korotkov, Amit Langote,
Andrew Dunstan)
</para>
<para>
The <link linkend="functions-sqljson-misc"><literal>IS
JSON</literal></link> checks include checks for values, arrays,
objects, scalars, and unique keys.
</para>
</listitem>
<!--
Author: John Naylor <john.naylor@postgresql.org>
2022-09-02 [0a8de93a4] Speed up lexing of long JSON strings
-->
<listitem>
<para>
Allow <acronym>JSON</acronym> string parsing to use vector
operations (John Naylor)
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-01-19 [5a617d75d] Fix ts_headline() to handle ORs and phrase queries more
-->
<listitem>
<para>
Improve the handling of full text highlighting function <link
linkend="textsearch-functions-table"><function>ts_headline()</function></link>
for <literal>OR</literal> and <literal>NOT</literal> expressions
(Tom Lane)
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-03-18 [75bd846b6] Add functions to do timestamptz arithmetic in a non-defa
-->
<listitem>
<para>
Add functions to add, subtract, and generate
<type>timestamptz</type> values in a specified time zone (Przemyslaw
Sztoch, Gurjeet Singh)
</para>
<para>
The functions are <link
linkend="functions-datetime-table"><function>date_add()</function></link>,
<function>date_subtract()</function>, and <link
linkend="functions-srf-series"><function>generate_series()</function></link>.
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2022-11-12 [533e02e92] Fix volatility marking of timestamptz_trunc_zone.
-->
<listitem>
<para>
Change <link
linkend="functions-datetime-table"><function>date_trunc(unit,
timestamptz, time_zone)</function></link> to be an immutable
function (Przemyslaw Sztoch)
</para>
<para>
This allows the creation of expression indexes using this function.
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2022-09-29 [0823d061b] Introduce SYSTEM_USER
-->
<listitem>
<para>
Add server variable <link
linkend="functions-info-session-table"><literal>SYSTEM_USER</literal></link>
(Bertrand Drouvot)
</para>
<para>
This reports the authentication method and its authenticated user.
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-04-07 [888f2ea0a] Add array_sample() and array_shuffle() functions.
-->
<listitem>
<para>
Add functions <link
linkend="array-functions-table"><function>array_sample()</function></link>
and <function>array_shuffle()</function> (Martin Kalcher)
</para>
</listitem>
<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2023-02-22 [2ddab010c] Implement ANY_VALUE aggregate
-->
<listitem>
<para>
Add aggregate function <link
linkend="functions-aggregate-table"><function>ANY_VALUE()</function></link>
which returns any value from a set (Vik Fearing)
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-01-09 [38d81760c] Invent random_normal() to provide normally-distributed r
-->
<listitem>
<para>
Add function <link
linkend="functions-math-random-table"><function>random_normal()</function></link>
to supply normally-distributed random numbers (Paul Ramsey)
</para>
</listitem>
<!--
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
2023-03-14 [d5d574146] Add support for the error functions erf() and erfc().
-->
<listitem>
<para>
Add error function <link
linkend="functions-math-func-table"><function>erf()</function></link>
and its complement <function>erfc()</function> (Dean Rasheed)
</para>
</listitem>
<!--
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
2022-10-20 [40c7fcbbe] Improve the accuracy of numeric power() for integer expo
-->
<listitem>
<para>
Improve the accuracy of numeric <link
linkend="functions-math-func-table"><function>power()</function></link>
for integer exponents (Dean Rasheed)
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-03-15 [483bdb2af] Support [NO] INDENT option in XMLSERIALIZE().
-->
<listitem>
<para>
Add <link
linkend="datatype-xml-creating"><function>XMLSERIALIZE()</function></link>
option <literal>INDENT</literal> to pretty-print its output
(Jim Jones)
</para>
</listitem>
<!--
Author: Jeff Davis <jdavis@postgresql.org>
2022-10-31 [10932ed5e] Enable pg_collation_actual_version() to work on the defa
-->
<listitem>
<para>
Change <link
linkend="functions-admin-collation"><function>pg_collation_actual_version()</function></link>
to return a reasonable value for the default collation (Jeff Davis)
</para>
<para>
Previously it returned <literal>NULL</literal>.
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2022-07-29 [283129e32] Support pg_read_[binary_]file (filename, missing_ok).
-->
<listitem>
<para>
Allow <link
linkend="functions-admin-genfile-table"><function>pg_read_file()</function></link>
and <function>pg_read_binary_file()</function> to ignore missing
files (Kyotaro Horiguchi)
</para>
</listitem>
<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2023-03-07 [ce1215d9b] Add support for unit "B" to pg_size_bytes()
-->
<listitem>
<para>
Add byte specification (<literal>B</literal>) to <link
linkend="functions-admin-dbsize"><function>pg_size_bytes()</function></link>
(Peter Eisentraut)
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2022-12-27 [3ea7329c9] Simplify the implementations of the to_reg* functions.
-->
<listitem>
<para>
Allow <link
linkend="functions-info-catalog-table"><function>to_reg</function></link>*
functions to accept numeric <acronym>OID</acronym>s as input
(Tom Lane)
</para>
</listitem>
</itemizedlist>
</sect3>
<sect3 id="release-16-plpgsql">
<title><link linkend="plpgsql">PL/pgSQL</link></title>
<itemizedlist>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-04-04 [d3d53f955] Add a way to get the current function's OID in pl/pgsql.
-->
<listitem>
<para>
Add the ability to get the current function's <acronym>OID</acronym>
in <application>PL/pgSQL</application> (Pavel Stehule)
</para>
<para>
This is accomplished with <link
linkend="plpgsql-statements-diagnostics"><command>GET DIAGNOSTICS
variable = PG_ROUTINE_OID</command></link>.
</para>
</listitem>
</itemizedlist>
</sect3>
<sect3 id="release-16-libpq">
<title><link linkend="libpq">libpq</link></title>
<itemizedlist>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2023-03-14 [3a465cc67] libpq: Add support for require_auth to control authorize
-->
<listitem>
<para>
Add <application>libpq</application> connection option <link
linkend="libpq-connect-require-auth"><option>require_auth</option></link>
to specify a list of acceptable authentication methods (Jacob
Champion)
</para>
<para>
This can also be used to disallow certain authentication methods.
</para>
</listitem>
<!--
Author: Daniel Gustafsson <dgustafsson@postgresql.org>
2023-03-29 [7f5b19817] Support connection load balancing in libpq
Author: Fujii Masao <fujii@postgresql.org>
2023-04-21 [0a16512d4] doc: Add documentation for PGLOADBALANCEHOSTS environmen
-->
<listitem>
<para>
Allow multiple <application>libpq</application>-specified hosts
to be randomly selected (Jelte Fennema)
</para>
<para>
This is enabled with <link
linkend="libpq-connect-load-balance-hosts"><literal>load_balance_hosts=random</literal></link>
and can be used for load balancing.
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2023-03-24 [36f40ce2d] libpq: Add sslcertmode option to control client certific
-->
<listitem>
<para>
Add <application>libpq</application> option <link
linkend="libpq-connect-sslcertmode"><option>sslcertmode</option></link>
to control transmission of the client certificate (Jacob Champion)
</para>
<para>
The option values are <literal>disable</literal>,
<literal>allow</literal>, and <literal>require</literal>.
</para>
</listitem>
<!--
Author: Daniel Gustafsson <dgustafsson@postgresql.org>
2023-04-05 [8eda73146] Allow to use system CA pool for certificate verification
-->
<listitem>
<para>
Allow <application>libpq</application> to use the system certificate
pool for certificate verification (Jacob Champion, Thomas Habets)
</para>
<para>
This is enabled with <link
linkend="libpq-connect-sslrootcert"><literal>sslrootcert=system</literal></link>,
which also enables <link
linkend="libpq-connect-sslmode"><literal>sslmode=verify-full</literal></link>.
</para>
</listitem>
</itemizedlist>
</sect3>
<sect3 id="release-16-client-apps">
<title>Client Applications</title>
<itemizedlist>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2022-07-12 [83f1c7b74] Fix ECPG's handling of type names that match SQL keyword
-->
<listitem>
<para>
Allow <link linkend="ecpg"><command>ECPG</command></link>
variable declarations to use typedef names that match unreserved
<acronym>SQL</acronym> keywords (Tom Lane)
</para>
<para>
This change does prevent keywords which match C typedef names from
being processed as keywords in later <command>EXEC SQL</command>
blocks.
</para>
</listitem>
</itemizedlist>
<sect4 id="release-16-psql">
<title><xref linkend="app-psql"/></title>
<itemizedlist>
<!--
Author: Andrew Dunstan <andrew@dunslane.net>
2022-07-25 [a45388d6e] Add xheader_width pset option to psql
-->
<listitem>
<para>
Allow <application>psql</application> to control the maximum
width of header lines in expanded format (Platon Pronko)
</para>
<para>
This is controlled by <link
linkend="app-psql-meta-command-pset-xheader-width"><option>xheader_width</option></link>.
</para>
</listitem>
<!--
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
2023-01-07 [d913928c9] psql: Add support for \dpS and \zS.
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-07-19 [d65ddaca9] Add psql \drg command to display role
-->
<listitem>
<para>
Add <application>psql</application> command <link
linkend="app-psql-meta-command-drg"><command>\drg</command></link>
to show role membership details (Pavel Luzanov)
</para>
<para>
The <literal>Member of</literal> output column has been removed
from <command>\du</command> and <command>\dg</command> because
this new command displays this informaion in more detail.
</para>
</listitem>
<!--
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
2023-01-07 [d913928c9] psql: Add support for \dpS and \zS.
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-07-19 [d65ddaca9] Add psql \drg command to display role
-->
<listitem>
<para>
Allow <application>psql</application>'s access privilege commands
to show system objects (Nathan Bossart)
</para>
<para>
The options are <link
linkend="app-psql-meta-command-dp-lc"><command>\dpS</command></link>
and <link
linkend="app-psql-meta-command-z"><command>\zS</command></link>.
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2022-11-08 [bd95816f7] psql: Add information in \d+ about foreign partitions an
-->
<listitem>
<para>
Add <literal>FOREIGN</literal> designation
to <application>psql</application> <link
linkend="app-psql-meta-command-d"><command>\d+</command></link>
for foreign table children and partitions (Ian Lawrence Barwick)
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-03-02 [3dfae91f7] Show "internal name" not "source code" in psql's \df+ co
-->
<listitem>
<para>
Prevent <link
linkend="app-psql-meta-command-df-uc"><command>\df+</command></link>
from showing function source code (Isaac Morland)
</para>
<para>
Function bodies are more easily viewed with <link
linkend="app-psql-meta-command-sf"><command>\sf</command></link>.
</para>
</listitem>
<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2022-11-15 [5b66de343] psql: Add command to use extended query protocol
-->
<listitem>
<para>
Allow <application>psql</application> to submit queries using
the extended query protocol (Peter Eisentraut)
</para>
<para>
Passing arguments to such queries is done
using the new <application>psql</application> <link
linkend="app-psql-meta-command-bind"><command>\bind</command></link>
command.
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-04-06 [00beecfe8] psql: add an optional execution-count limit to \watch.
-->
<listitem>
<para>
Allow <application>psql</application> <link
linkend="app-psql-meta-command-watch"><command>\watch</command></link>
to limit the number of executions (Andrey Borodin)
</para>
<para>
The <command>\watch</command> options can now be named when
specified.
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2023-03-16 [6f9ee74d4] Improve handling of psql \watch's interval argument
-->
<listitem>
<para>
Detect invalid values for <application>psql</application> <link
linkend="app-psql-meta-command-watch"><command>\watch</command></link>,
and allow zero to specify no delay (Andrey Borodin)
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-03-21 [b0d8f2d98] Add SHELL_ERROR and SHELL_EXIT_CODE magic variables to p
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-04-06 [31ae2aa9d] psql: set SHELL_ERROR and SHELL_EXIT_CODE in more places
-->
<listitem>
<para>
Allow <application>psql</application> scripts to obtain the exit
status of shell commands and queries
(Corey Huinker, Tom Lane)
</para>
<para>
The new <application>psql</application> control variables are <link
linkend="app-psql-variables-shell-error"><literal>SHELL_ERROR</literal></link>
and <link
linkend="app-psql-variables-shell-exit-code"><literal>SHELL_EXIT_CODE</literal></link>.
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2022-08-15 [f6c750d31] Improve tab completion of ALTER TYPE in psql
Author: Michael Paquier <michael@paquier.xyz>
2022-09-06 [4cbe57974] Add psql tab compression for SET COMPRESSION with ALTER
Author: Michael Paquier <michael@paquier.xyz>
2022-09-10 [6afcab6ac] Add psql tab compression for ALTER TABLE .. { OF | NOT O
Author: Michael Paquier <michael@paquier.xyz>
2022-10-05 [9aa58d48f] Add a few new patterns to the tab completion of psql
Author: Michael Paquier <michael@paquier.xyz>
2022-10-24 [3cf2f7af7] Improve tab completion for ALTER STATISTICS <name> SET i
Author: Peter Eisentraut <peter@eisentraut.org>
2022-11-01 [2ea5de296] psql: Improve tab completion for ALTER TABLE on identity
Author: Michael Paquier <michael@paquier.xyz>
2022-11-18 [07f7237c2] psql: Improve tab completion for GRANT/REVOKE
Author: Michael Paquier <michael@paquier.xyz>
2022-12-12 [9d0cf5749] Add support for GRANT SET in psql tab completion
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
2023-01-06 [a3bc631ea] Improve tab completion for ALTER FUNCTION/PROCEDURE/ROUT
Author: Michael Paquier <michael@paquier.xyz>
2023-01-12 [2ff5ca86e] Add support for tab completion after ALTER EXTENSION ADD
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-04-19 [9e1e9d656] Add missed case for tab completion of GRANT/REVOKE MAINT
Author: Amit Kapila <akapila@postgresql.org>
2023-04-07 [96c498d2f] Add tab-completion for newly added SUBSCRIPTION options.
-->
<listitem>
<para>
Various <application>psql</application> tab completion improvements
(Vignesh C, Aleksander Alekseev, Dagfinn Ilmari Mannsåker,
Shi Yu, Michael Paquier, Ken Kato, Peter Smith)
</para>
</listitem>
</itemizedlist>
</sect4>
<sect4 id="release-16-pgdump">
<title><link linkend="app-pgdump"><application>pg_dump</application></link></title>
<itemizedlist>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-03-14 [a563c24c9] Allow pg_dump to include/exclude child tables automatica
-->
<listitem>
<para>
Add <application>pg_dump</application> control of dumping child
tables and partitions (Gilles Darold)
</para>
<para>
The new options are <option>--table-and-children</option>,
<option>--exclude-table-and-children</option>, and
<option>--exclude-table-data-and-children</option>.
</para>
</listitem>
<!--
Author: Tomas Vondra <tomas.vondra@postgresql.org>
2023-02-23 [0da243fed] Add LZ4 compression to pg_dump
Author: Tomas Vondra <tomas.vondra@postgresql.org>
2023-04-01 [0070b66fe] pg_dump: Use only LZ4 frame format for compression
Author: Tomas Vondra <tomas.vondra@postgresql.org>
2023-04-05 [84adc8e20] pg_dump: Add support for zstd compression-->
<listitem>
<para>
Add <application>LZ4</application> and
<application>Zstandard</application> compression to
<application>pg_dump</application> (Georgios Kokolatos, Justin
Pryzby)
</para>
</listitem>
<!--
Author: Tomas Vondra <tomas.vondra@postgresql.org>
2023-04-06 [2820adf77] Support long distance matching for zstd compression
-->
<listitem>
<para>
Allow <application>pg_dump</application> and <link
linkend="app-pgbasebackup"><application>pg_basebackup</application></link>
to use <literal>long</literal> mode for compression (Justin Pryzby)
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2022-12-02 [5e73a6048] Switch pg_dump to use compression specifications
-->
<listitem>
<para>
Improve <application>pg_dump</application> to accept a more
consistent compression syntax (Georgios Kokolatos)
</para>
<para>
Options like <option>--compress=gzip:5</option>.
</para>
</listitem>
</itemizedlist>
</sect4>
</sect3>
<sect3 id="release-16-server-apps">
<title>Server Applications</title>
<itemizedlist>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us> 2023-03-22
[3e51b278d] Add "-c name=value" switch to initdb.
-->
<listitem>
<para>
Add <link
linkend="app-initdb"><application>initdb</application></link>
option to set server variables for the duration of
<application>initdb</application> and all future server starts
(Tom Lane)
</para>
<para>
The option is <option>-c name=value</option>.
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2022-07-13 [08951a7c9] createuser: Add support for more clause types through ne
Author: Nathan Bossart <nathan@postgresql.org>
2023-05-21 [2dcd1578c] Rename some createuser options.
-->
<listitem>
<para>
Add options to <link
linkend="app-createuser"><application>createuser</application></link>
to control more user options (Shinya Kato)
</para>
<para>
Specifically, the new options control the valid-until date,
bypassing of row-level security, and role membership.
</para>
</listitem>
<!--
Author: Nathan Bossart <nathan@postgresql.org>
2023-05-21 [2dcd1578c] Rename some createuser options.
Author: Nathan Bossart <nathan@postgresql.org>
2023-05-23 [381d19b3e] Document deprecated createuser option.
-->
<listitem>
<para>
Deprecate <link
linkend="app-createuser"><application>createuser</application></link>
option <option>--role</option> (Nathan Bossart)
</para>
<para>
This option could be easily confused with new
<application>createuser</application> role membership options,
so option <option>--member-of</option> has been added with the
same functionality. The <option>--role</option> option can still
be used.
</para>
</listitem>
<!--
Author: Andrew Dunstan <andrew@dunslane.net>
2022-07-31 [7781f4e3e] Add - -schema and - -exclude-schema options to vacuumdb.
-->
<listitem>
<para>
Allow control of <link
linkend="app-vacuumdb"><application>vacuumdb</application></link>
schema processing (Gilles Darold)
</para>
<para>
These are controlled by options <option>--schema</option> and
<option>--exclude-schema</option>.
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-01-06 [a46a7011b] Add options to control whether VACUUM runs vac_update_da
-->
<listitem>
<para>
Use new <link linkend="sql-vacuum"><command>VACUUM</command></link>
options to improve the performance of <link
linkend="app-vacuumdb"><application>vacuumdb</application></link>
(Tom Lane, Nathan Bossart)
</para>
</listitem>
<!--
Author: Jeff Davis <jdavis@postgresql.org>
2023-03-09 [9637badd9] pg_upgrade: copy locale and encoding information to new
-->
<listitem>
<para>
Have <link
linkend="pgupgrade"><application>pg_upgrade</application></link>
set the new cluster's locale and encoding (Jeff Davis)
</para>
<para>
This removes the requirement that the new cluster be created with
the same locale and encoding settings.
</para>
</listitem>
<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2022-12-16 [746915c68] pg_upgrade: Add - -copy option
-->
<listitem>
<para>
Add <link
linkend="pgupgrade"><application>pg_upgrade</application></link>
option to specify the default transfer mode (Peter Eisentraut)
</para>
<para>
The option is <option>--copy</option>.
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2022-11-30 [d18655cc0] Refactor code parsing compression option values (-Z/- -co
-->
<listitem>
<para>
Improve <link
linkend="app-pgbasebackup"><application>pg_basebackup</application></link>
to accept numeric compression options (Georgios Kokolatos,
Michael Paquier)
</para>
<para>
Options like <option>--compress=server-5</option> are now supported.
</para>
</listitem>
<!--
Author: Robert Haas <rhaas@postgresql.org>
2023-04-18 [363e8f911] Fix pg_basebackup with in-place tablespaces some more.
-->
<listitem>
<para>
Fix <link
linkend="app-pgbasebackup"><application>pg_basebackup</application></link>
to handle tablespaces stored in the <envar>PGDATA</envar> directory
(Robert Haas)
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2022-12-27 [d497093cb] pg_waldump: Add - -save-fullpage=PATH to save full page i
-->
<listitem>
<para>
Add <link
linkend="pgwaldump"><application>pg_waldump</application></link>
option <option>--save-fullpage</option> to dump full page images
(David Christensen)
</para>
</listitem>
<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2023-03-21 [4c8044c04] pg_waldump: Allow hexadecimal values for -t/- -timeline o
-->
<listitem>
<para>
Allow <link
linkend="pgwaldump"><application>pg_waldump</application></link>
options <option>-t</option>/<option>--timeline</option> to accept
hexadecimal values (Peter Eisentraut)
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2023-02-06 [d07c2948b] Add support for progress reporting to pg_verifybackup
-->
<listitem>
<para>
Add support for progress reporting to <link
linkend="app-pgverifybackup"><application>pg_verifybackup</application></link>
(Masahiko Sawada)
</para>
</listitem>
<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
2023-02-23 [009eeee74] pg_rewind: Fix determining TLI when server was just prom
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
2023-02-27 [0a0500207] pg_rewind: Remove notice in docs about running CHECKPOIN
-->
<listitem>
<para>
Allow <link
linkend="app-pgrewind"><application>pg_rewind</application></link>
to properly track timeline changes (Heikki Linnakangas)
</para>
<para>
Previously if <application>pg_rewind</application> was run after
a timeline switch but before a checkpoint was issued, it might
incorrectly determine that a rewind was unnecessary.
</para>
</listitem>
<!--
Author: Daniel Gustafsson <dgustafsson@postgresql.org>
2022-09-14 [8b60db774] Handle SIGTERM in pg_receivewal and pg_recvlogical
-->
<listitem>
<para>
Have <link
linkend="app-pgreceivewal"><application>pg_receivewal</application></link>
and <link
linkend="app-pgrecvlogical"><application>pg_recvlogical</application></link>
cleanly exit on <literal>SIGTERM</literal> (Christoph Berg)
</para>
<para>
This signal is often used by <application>systemd</application>.
</para>
</listitem>
</itemizedlist>
</sect3>
<sect3 id="release-16-source-code">
<title>Source Code</title>
<itemizedlist>
<!--
Author: Jeff Davis <jdavis@postgresql.org>
2023-04-18 [fcb21b3ac] Build ICU support by default.
-->
<listitem>
<para>
Build <acronym>ICU</acronym> support by default (Jeff Davis)
</para>
<para>
This removes <link linkend="installation">build
flag</link> <option>--with-icu</option> and adds flag
<option>--without-icu</option>.
</para>
</listitem>
<!--
Author: John Naylor <john.naylor@postgresql.org>
2022-08-04 [56f2c7b58] Support SSE2 intrinsics where available
-->
<listitem>
<para>
Add support for SSE2 (Streaming <acronym>SIMD</acronym> Extensions
2) vector operations on x86-64 architectures (John Naylor)
</para>
</listitem>
<!--
Author: John Naylor <john.naylor@postgresql.org>
2022-08-29 [82739d4a8] Use ARM Advanced SIMD (NEON) intrinsics where available
-->
<listitem>
<para>
Add support for Advanced <acronym>SIMD</acronym> (Single
Instruction Multiple Data) (<acronym>NEON</acronym>) instructions
on <acronym>ARM</acronym> architectures (Nathan Bossart)
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2022-08-28 [36389a060] Enable RandomizedBaseAddress (ASLR) on Windows with MSVC
-->
<listitem>
<para>
Have <systemitem class="osname">Windows</systemitem>
binaries built with <productname>MSVC</productname> use
<literal>RandomizedBaseAddress</literal> (<acronym>ASLR</acronym>)
(Michael Paquier)
</para>
<para>
This was already enabled on <productname>MinGW</productname> builds.
</para>
</listitem>
<!--
Author: Andres Freund <andres@anarazel.de>
2022-07-17 [089480c07] Default to hidden visibility for extension libraries whe
Author: Andres Freund <andres@anarazel.de>
2022-07-17 [8cf64d35e] Mark all symbols exported from extension libraries PGDLL
-->
<listitem>
<para>
Prevent extension libraries from exporting their symbols by default
(Andres Freund, Tom Lane)
</para>
<para>
Functions that need to be called from the core backend
or other extensions must now be explicitly marked
<literal>PGDLLEXPORT</literal>.
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2022-07-07 [495ed0ef2] Make Windows 10 the minimal runtime requirement for WIN3
-->
<listitem>
<para>
Require <systemitem class="osname">Windows 10</systemitem> or
newer versions (Michael Paquier, Juan José Santamaría Flecha)
</para>
<para>
Previously <systemitem class="osname">Windows Vista</systemitem> and
<systemitem class="osname">Windows XP</systemitem> were supported.
</para>
</listitem>
<!--
Author: John Naylor <john.naylor@postgresql.org>
2022-09-14 [4c1532763] Bump minimum Perl version to 5.14
-->
<listitem>
<para>
Require <productname>Perl</productname> version 5.14 or later
(John Naylor)
</para>
</listitem>
<!--
Author: John Naylor <john.naylor@postgresql.org>
2022-09-09 [b086a47a2] Bump minimum version of Bison to 2.3
-->
<listitem>
<para>
Require <productname>Bison</productname> version 2.3 or later
(John Naylor)
</para>
</listitem>
<!--
Author: John Naylor <john.naylor@postgresql.org>
2022-09-09 [8b878bffa] Bump minimum version of Flex to 2.5.35
-->
<listitem>
<para>
Require <productname>Flex</productname> version 2.5.35 or later
(John Naylor)
</para>
</listitem>
<!--
Author: Stephen Frost <sfrost@snowman.net>
2023-04-13 [f7431bca8] Explicitly require MIT Kerberos for GSSAPI
-->
<listitem>
<para>
Require <acronym>MIT</acronym> Kerberos for
<acronym>GSSAPI</acronym> support (Stephen Frost)
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2022-07-14 [6203583b7] Remove support for Visual Studio 2013
-->
<listitem>
<para>
Remove support for <productname>Visual Studio 2013</productname>
(Michael Paquier)
</para>
</listitem>
<!--
Author: Thomas Munro <tmunro@postgresql.org>
2022-07-08 [9db300ce6] Remove HP-UX port.
-->
<listitem>
<para>
Remove support for <systemitem class="osname">HP-UX</systemitem>
(Thomas Munro)
</para>
</listitem>
<!--
Author: Thomas Munro <tmunro@postgresql.org>
2022-07-08 [0ad5b48e5] Remove HP/Intel Itanium support.
-->
<listitem>
<para>
Remove support for <productname>HP/Intel Itanium</productname>
(Thomas Munro)
</para>
</listitem>
<!--
Author: Thomas Munro <tmunro@postgresql.org>
2022-07-12 [718aa43a4] Further tidy-up for old CPU architectures.
Author: Thomas Munro <tmunro@postgresql.org>
2022-07-12 [14168d3c6] Doc: Acknowledge historically supported CPUs and OSes.
-->
<listitem>
<para>
Remove support for <productname>M68K</productname>,
<productname>M88K</productname>, <productname>M32R</productname>,
and <productname>SuperH</productname> <acronym>CPU</acronym>
architectures (Thomas Munro)
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2023-03-17 [98ae2c84a] libpq: Remove code for SCM credential authentication
-->
<listitem>
<para>
Remove <link linkend="libpq"><application>libpq</application></link>
support for <acronym>SCM</acronym> credential authentication
(Michael Paquier)
</para>
<para>
Backend support for this authentication method was removed in
<productname>PostgresSQL</productname> 9.1.
</para>
</listitem>
<!--
Author: Andres Freund <andres@anarazel.de>
2022-09-21 [e6927270c] meson: Add initial version of meson based build system
-->
<listitem>
<para>
Add <link
linkend="install-meson"><application>meson</application></link>
build system (Andres Freund, Nazir Bilal Yavuz, Peter Eisentraut)
</para>
<para>
This eventually will replace the <productname>Autoconf</productname>
and <systemitem class="osname">Windows</systemitem>-based
<productname>MSVC</productname> build systems.
</para>
</listitem>
<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2022-10-20 [c8e4030d1] Make finding openssl program a configure or meson option
-->
<listitem>
<para>
Allow control of the location of the
<application>openssl</application> binary used by the build system
(Peter Eisentraut)
</para>
<para>
Make finding <application>openssl</application>
program a <application>configure</application> or
<application>meson</application> option
</para>
</listitem>
<!--
Author: Andres Freund <andres@anarazel.de>
2022-12-07 [d3b111e32] Add option to specify segment size in blocks
-->
<listitem>
<para>
Add build option to allow testing of small table segment sizes
(Andres Freund)
</para>
<para>
The build options are <link
linkend="configure-option-with-segsize"><option>--with-segsize-blocks</option></link>
and <option>-Dsegsize_blocks</option>.
</para>
</listitem>
<!--
Author: Andrew Dunstan <andrew@dunslane.net>
2023-01-23 [b90f0b574] Add non-destructive modes to pgindent
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-01-23 [62e1e28bf] Fix pgindent - -show-diff option.
Author: Andrew Dunstan <andrew@dunslane.net>
2023-01-24 [124937163] Improve exclude pattern file processing in pgindent
Author: Andrew Dunstan <andrew@dunslane.net>
2023-01-27 [a1c4cd6f2] Allow multiple - -excludes options in pgindent
Author: Andrew Dunstan <andrew@dunslane.net>
2023-02-08 [068a243b7] pgindent: more ways to find files to indent
Author: Andrew Dunstan <andrew@dunslane.net>
2023-02-12 [dab07e8c6] pgindent: filter files for the - -commit option
Author: Andrew Dunstan <andrew@dunslane.net>
2023-02-13 [b16259b3c] Remove obsolete pgindent options - -code-base and - -build
-->
<listitem>
<para>
Add <link
linkend="source"><application>pgindent</application></link> options
(Andrew Dunstan)
</para>
<para>
The new options are <option>--show-diff</option>,
<option>--silent-diff</option>, <option>--commit</option>,
and <option>--help</option>, and allow multiple
<option>--exclude</option> options. Also require the typedef file
to be explicitly specified. Options <option>--code-base</option>
and <option>--build</option> were also removed.
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-02-12 [4e831f4ce] Import pg_bsd_indent sources.
-->
<listitem>
<para>
Add <link
linkend="source"><application>pg_bsd_indent</application></link>
source code to the main tree (Tom Lane)
</para>
</listitem>
<!--
Author: Tatsuo Ishii <ishii@postgresql.org>
2022-10-19 [d1e2a380c] Enhance make_ctags and make_etags.
-->
<listitem>
<para>
Improve <application>make_ctags</application> and
<application>make_etags</application> (Yugo Nagata)
</para>
</listitem>
<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2023-03-28 [90189eefc] Save a few bytes in pg_attribute
-->
<listitem>
<para>
Adjust <link
linkend="catalog-pg-attribute"><structname>pg_attribute</structname></link>
columns for efficiency (Peter Eisentraut)
</para>
</listitem>
</itemizedlist>
</sect3>
<sect3 id="release-16-modules">
<title>Additional Modules</title>
<itemizedlist>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2022-09-02 [ff720a597] Fix planner to consider matches to boolean columns in ex
-->
<listitem>
<para>
Improve use of extension-based indexes on boolean columns (Zongliang
Quan, Tom Lane)
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-04-07 [a290378a3] Add support for Daitch-Mokotoff Soundex in contrib/fuzzy
-->
<listitem>
<para>
Add support for Daitch-Mokotoff Soundex to <link
linkend="fuzzystrmatch"><application>fuzzystrmatch</application></link>
(Dag Lem)
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2022-07-06 [d4bfe4128] autho_explain: Add GUC to log query parameters
-->
<listitem>
<para>
Allow <link
linkend="auto-explain"><application>auto_explain</application></link>
to log values passed to parameterized statements (Dagfinn Ilmari
Mannsåker)
</para>
<para>
This affects queries using server-side <link
linkend="sql-prepare"><command>PREPARE</command></link>/<link
linkend="sql-execute"><command>EXECUTE</command></link>
and client-side parse/bind. Logging is controlled by <link
linkend="auto-explain-configuration-parameters-log-parameter-max-length"><literal>auto_explain.log_parameter_max_length</literal></link>;
by default query parameters will be logged with no length
restriction.
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2023-01-26 [9d2d9728b] Make auto_explain print the query identifier in verbose
-->
<listitem>
<para>
Have <link
linkend="auto-explain"><application>auto_explain</application></link>'s
<option>log_verbose</option> mode honor the value of <link
linkend="guc-compute-query-id"><varname>compute_query_id</varname></link>
(Atsushi Torikoshi)
</para>
<para>
Previously even if
<varname>compute_query_id</varname> was enabled, <link
linkend="auto-explain-configuration-parameters-log-verbose"><option>log_verbose</option></link>
was not showing the query identifier.
</para>
</listitem>
<!--
Author: Andrew Dunstan <andrew@dunslane.net>
2023-01-06 [b1665bf01] Allow hyphens in ltree labels
-->
<listitem>
<para>
Change the maximum length of <link
linkend="ltree"><application>ltree</application></link> labels
from 256 to 1000 and allow hyphens (Garen Torikian)
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2023-03-08 [daa8365a9] Reflect normalization of query strings for utilities in
-->
<listitem>
<para>
Have <link
linkend="pgstatstatements"><structname>pg_stat_statements</structname></link>
normalize constants used in utility commands (Michael Paquier)
</para>
<para>
Previously constants appeared instead of placeholders, e.g.,
<literal>$1</literal>.
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2023-01-23 [c31cf1c03] pg_walinspect: Add pg_get_wal_fpi_info()
Author: Michael Paquier <michael@paquier.xyz>
2023-03-10 [9ecb134a9] pg_walinspect: pg_get_wal_fpi_info() -> pg_get_wal_block
Author: Peter Geoghegan <pg@bowt.ie>
2023-03-30 [122376f02] Show record information in pg_get_wal_block_info.
Author: Peter Geoghegan <pg@bowt.ie>
2023-03-31 [df4f3ab51] Add show_data option to pg_get_wal_block_info.
-->
<listitem>
<para>
Add <link
linkend="pgwalinspect"><application>pg_walinspect</application></link>
function <link
linkend="pgwalinspect-funcs-pg-get-wal-block-info"><function>pg_get_wal_block_info()</function></link>
to report <acronym>WAL</acronym> block information (Michael Paquier,
Melanie Plageman, Bharath Rupireddy)
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2023-03-14 [5c1b66280] Rework design of functions in pg_walinspect
-->
<listitem>
<para>
Change how <link
linkend="pgwalinspect"><application>pg_walinspect</application></link>
functions <link
linkend="pgwalinspect-funcs-pg-get-wal-records-info"><function>pg_get_wal_records_info()</function></link>
and <link
linkend="pgwalinspect-funcs-pg-get-wal-stats"><function>pg_get_wal_stats()</function></link>
interpret ending <acronym>LSN</acronym>s (Bharath Rupireddy)
</para>
<para>
Previously ending <acronym>LSN</acronym>s which represent
nonexistent <acronym>WAL</acronym> locations would generate
an error, while they will now be interpreted as the end of the
<acronym>WAL</acronym>.
</para>
</listitem>
<!--
Author: Peter Geoghegan <pg@bowt.ie>
2023-04-07 [7d8219a44] Show more detail in heapam rmgr descriptions.
Author: Peter Geoghegan <pg@bowt.ie>
2023-04-07 [1c453cfd8] Show more detail in nbtree rmgr descriptions.
Author: Peter Geoghegan <pg@bowt.ie>
2023-04-11 [96149a180] Fix Heap rmgr's desc output for infobits arrays.
Author: Peter Geoghegan <pg@bowt.ie>
2023-04-19 [50547a3fa] Fix wal_consistency_checking enhanced desc output.
-->
<listitem>
<para>
Add detailed descriptions of <acronym>WAL</acronym> records in <link
linkend="pgwalinspect"><application>pg_walinspect</application></link>
and <link
linkend="pgwaldump"><application>pg_waldump</application></link>
(Melanie Plageman, Peter Geoghegan)
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-01-02 [1fd3dd204] Add bt_multi_page_stats() function to contrib/pageinspec
-->
<listitem>
<para>
Add <link
linkend="pageinspect"><application>pageinspect</application></link>
function <link
linkend="pageinspect-b-tree-funcs"><function>bt_multi_page_stats()</function></link>
to report statistics on multiple pages (Hamid Akhtar)
</para>
<para>
This is similar to <function>bt_page_stats()</function> except it
can report on a range of pages.
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-01-02 [1fd3dd204] Add bt_multi_page_stats() function to contrib/pageinspec
-->
<listitem>
<para>
Add empty range output column to <link
linkend="pageinspect"><application>pageinspect</application></link>
function <link
linkend="pageinspect-brin-funcs"><function>brin_page_items()</function></link>
(Tomas Vondra)
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2023-02-17 [35739b87d] Redesign archive modules
-->
<listitem>
<para>
Redesign archive modules to be more flexible (Nathan Bossart)
</para>
<para>
Initialization changes will require modules written for older
versions of Postgres to be updated.
</para>
</listitem>
<!--
Author: Michael Paquier <michael@paquier.xyz>
2023-04-06 [1d477a907] Fix row tracking in pg_stat_statements with extended que
-->
<listitem>
<para>
Correct inaccurate <link
linkend="pgstatstatements"><application>pg_stat_statements</application></link>
row tracking extended query protocol statements (Sami Imseih)
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-04-07 [f3fa31327] Add pg_buffercache_usage_counts() to contrib/pg_bufferca
-->
<listitem>
<para>
Add <link
linkend="pgbuffercache"><application>pg_buffercache</application></link>
function <function>pg_buffercache_usage_counts()</function> to
report usage totals (Nathan Bossart)
</para>
</listitem>
<!--
Author: Andres Freund <andres@anarazel.de>
2022-10-13 [2589434ae] pg_buffercache: Add pg_buffercache_summary()
-->
<listitem>
<para>
Add <link
linkend="pgbuffercache"><application>pg_buffercache</application></link>
function <function>pg_buffercache_summary()</function> to report
summarized buffer statistics (Melih Mutlu)
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-03-20 [72a5b1fc8] Add @extschema:name@ and no_relocate options to extensio
-->
<listitem>
<para>
Allow the schemas of required extensions to be
referenced in extension scripts using the new syntax
<literal>@extschema:referenced_extension_name@</literal>
(Regina Obe)
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2023-03-20 [72a5b1fc8] Add @extschema:name@ and no_relocate options to extensio
-->
<listitem>
<para>
Allow required extensions to
be marked as non-relocatable using <link
linkend="extend-extensions-files-no-relocate"><literal>no_relocate</literal></link>
(Regina Obe)
</para>
<para>
This allows <literal>@extschema:referenced_extension_name@</literal>
to be treated as a constant for the lifetime of the extension.
</para>
</listitem>
</itemizedlist>
<sect4 id="release-16-pgfdw">
<title><link linkend="postgres-fdw"><application>postgres_fdw</application></link></title>
<itemizedlist>
<!--
Author: Etsuro Fujita <efujita@postgresql.org>
2023-04-06 [983ec2300] postgres_fdw: Add support for parallel abort.
-->
<listitem>
<para>
Allow <application>postgres_fdw</application> to do aborts in
parallel (Etsuro Fujita)
</para>
<para>
This is enabled with
<application>postgres_fdw</application> option <link
linkend="postgres-fdw-options-transaction-management"><option>parallel_abort</option></link>.
</para>
</listitem>
<!--
Author: Tomas Vondra <tomas.vondra@postgresql.org>
2022-12-30 [8ad51b5f4] Sample postgres_fdw tables remotely during ANALYZE
-->
<listitem>
<para>
Make <link linkend="sql-analyze"><command>ANALYZE</command></link>
on foreign <application>postgres_fdw</application> tables more
efficient (Tomas Vondra)
</para>
<para>
The <application>postgres_fdw</application> option <link
linkend="postgres-fdw-options-cost-estimation"><option>analyze_sampling</option></link>
controls the sampling method.
</para>
</listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2022-07-17 [31e5b5029] postgres_fdw: be more wary about shippability of reg* co
-->
<listitem>
<para>
Restrict shipment of <link
linkend="datatype-oid"><type>reg</type></link>* type constants
in <application>postgres_fdw</application> to those referencing
built-in objects or extensions marked as shippable (Tom Lane)
</para>
</listitem>
<!--
Author: Andres Freund <andres@anarazel.de>
2023-01-23 [e4602483e] dblink, postgres_fdw: Handle interrupts during connectio
-->
<listitem>
<para>
Have <application>postgres_fdw</application> and <link
linkend="dblink"><application>dblink</application></link> handle
interrupts during connection establishment (Andres Freund)
</para>
</listitem>
</itemizedlist>
</sect4>
</sect3>
</sect2>
<sect2 id="release-16-acknowledgements">
<title>Acknowledgments</title>
<para>
The following individuals (in alphabetical order) have contributed
to this release as patch authors, committers, reviewers, testers,
or reporters of issues.
</para>
<simplelist>
<member>Abhijit Menon-Sen</member>
<member>Adam Mackler</member>
<member>Adrian Klaver</member>
<member>Ahsan Hadi</member>
<member>Ajin Cherian</member>
<member>Ajit Awekar</member>
<member>Alan Hodgson</member>
<member>Aleksander Alekseev</member>
<member>Alex Denman</member>
<member>Alex Kozhemyakin</member>
<member>Alexander Korolev</member>
<member>Alexander Korotkov</member>
<member>Alexander Lakhin</member>
<member>Alexander Pyhalov</member>
<member>Alexey Borzov</member>
<member>Alexey Ermakov</member>
<member>Alexey Makhmutov</member>
<member>Álvaro Herrera</member>
<member>Amit Kapila</member>
<member>Amit Khandekar</member>
<member>Amit Langote</member>
<member>Amul Sul</member>
<member>Anastasia Lubennikova</member>
<member>Anban Company</member>
<member>Andreas Dijkman</member>
<member>Andreas Karlsson</member>
<member>Andreas Scherbaum</member>
<member>Andrei Zubkov</member>
<member>Andres Freund</member>
<member>Andrew Alsup</member>
<member>Andrew Bille</member>
<member>Andrew Dunstan</member>
<member>Andrew Gierth</member>
<member>Andrew Kesper</member>
<member>Andrey Borodin</member>
<member>Andrey Lepikhov</member>
<member>Andrey Sokolov</member>
<member>Ankit Kumar Pandey</member>
<member>Ante Kresic</member>
<member>Anton Melnikov</member>
<member>Anton Sidyakin</member>
<member>Anton Voloshin</member>
<member>Antonin Houska</member>
<member>Arne Roland</member>
<member>Artem Anisimov</member>
<member>Arthur Zakirov</member>
<member>Ashutosh Bapat</member>
<member>Ashutosh Sharma</member>
<member>Asim Praveen</member>
<member>Atsushi Torikoshi</member>
<member>Ayaki Tachikake</member>
<member>Balazs Szilfai</member>
<member>Benoit Lobréau</member>
<member>Bernd Helmle</member>
<member>Bertrand Drouvot</member>
<member>Bharath Rupireddy</member>
<member>Bilva Sanaba</member>
<member>Bob Krier</member>
<member>Boris Zentner</member>
<member>Brad Nicholson</member>
<member>Brar Piening</member>
<member>Bruce Momjian</member>
<member>Bruno da Silva</member>
<member>Carl Sopchak</member>
<member>Cary Huang</member>
<member>Changhong Fei</member>
<member>Chris Travers</member>
<member>Christoph Berg</member>
<member>Christophe Pettus</member>
<member>Corey Huinker</member>
<member>Craig Ringer</member>
<member>Curt Kolovson</member>
<member>Dag Lem</member>
<member>Dagfinn Ilmari Mannsåker</member>
<member>Daniel Gustafsson</member>
<member>Daniel Vérité</member>
<member>Daniel Watzinger</member>
<member>Daniel Westermann</member>
<member>Daniele Varrazzo</member>
<member>Daniil Anisimov</member>
<member>Danny Shemesh</member>
<member>Dave Page</member>
<member>David Christensen</member>
<member>David G. Johnston</member>
<member>David Geier</member>
<member>David Gilman</member>
<member>David Kimura</member>
<member>David Rowley</member>
<member>David Steele</member>
<member>David Turon</member>
<member>David Zhang</member>
<member>Davinder Singh</member>
<member>Dean Rasheed</member>
<member>Denis Laxalde</member>
<member>Dilip Kumar</member>
<member>Dimos Stamatakis</member>
<member>Dmitriy Kuzmin</member>
<member>Dmitry Astapov</member>
<member>Dmitry Dolgov</member>
<member>Dmitry Koval</member>
<member>Dong Wook Lee</member>
<member>Dongming Liu</member>
<member>Drew DeVault</member>
<member>Duncan Sands</member>
<member>Ed Maste</member>
<member>Egor Chindyaskin</member>
<member>Ekaterina Kiryanova</member>
<member>Elena Indrupskaya</member>
<member>Emmanuel Quincerot</member>
<member>Eric Mutta</member>
<member>Erik Rijkers</member>
<member>Erki Eessaar</member>
<member>Erwin Brandstetter</member>
<member>Etsuro Fujita</member>
<member>Eugeny Zhuzhnev</member>
<member>Euler Taveira</member>
<member>Evan Jones</member>
<member>Evgeny Morozov</member>
<member>Fabrízio de Royes Mello</member>
<member>Farias de Oliveira</member>
<member>Florin Irion</member>
<member>Franz-Josef Färber</member>
<member>Garen Torikian</member>
<member>Georgios Kokolatos</member>
<member>Gilles Darold</member>
<member>Greg Stark</member>
<member>Guillaume Lelarge</member>
<member>Gunnar Bluth</member>
<member>Gunnar Morling</member>
<member>Gurjeet Singh</member>
<member>Haiyang Wang</member>
<member>Haiying Tang</member>
<member>Hamid Akhtar</member>
<member>Hans Buschmann</member>
<member>Hao Wu</member>
<member>Hayato Kuroda</member>
<member>Heath Lord</member>
<member>Heikki Linnakangas</member>
<member>Himanshu Upadhyaya</member>
<member>Hisahiro Kauchi</member>
<member>Hongyu Song</member>
<member>Hubert Lubaczewski</member>
<member>Hung Nguyen</member>
<member>Ian Barwick</member>
<member>Ibrar Ahmed</member>
<member>Ilya Gladyshev</member>
<member>Ilya Nenashev</member>
<member>Isaac Morland</member>
<member>Israel Barth Rubio</member>
<member>Jacob Champion</member>
<member>Jacob Speidel</member>
<member>Jaime Casanova</member>
<member>Jakub Wartak</member>
<member>James Coleman</member>
<member>James Inform</member>
<member>James Vanns</member>
<member>Jan Wieck</member>
<member>Japin Li</member>
<member>Jeevan Ladhe</member>
<member>Jeff Davis</member>
<member>Jeff Janes</member>
<member>Jehan-Guillaume de Rorthais</member>
<member>Jelte Fennema</member>
<member>Jian He</member>
<member>Jim Jones</member>
<member>Jinbao Chen</member>
<member>Joe Conway</member>
<member>Joel Jacobson</member>
<member>John Naylor</member>
<member>Jonathan Katz</member>
<member>Josef Simanek</member>
<member>Joseph Koshakow</member>
<member>Juan José Santamaría Flecha</member>
<member>Julien Rouhaud</member>
<member>Julien Roze</member>
<member>Junwang Zhao</member>
<member>Justin Pryzby</member>
<member>Justin Zhang</member>
<member>Karina Litskevich</member>
<member>Karl O. Pinc</member>
<member>Keisuke Kuroda</member>
<member>Ken Kato</member>
<member>Kevin McKibbin</member>
<member>Kieran McCusker</member>
<member>Kirk Wolak</member>
<member>Konstantin Knizhnik</member>
<member>Koshi Shibagaki</member>
<member>Kotaro Kawamoto</member>
<member>Kui Liu</member>
<member>Kyotaro Horiguchi</member>
<member>Lakshmi Narayanan Sreethar</member>
<member>Laurence Parry</member>
<member>Laurenz Albe</member>
<member>Luca Ferrari</member>
<member>Lukas Fittl</member>
<member>Maciek Sakrejda</member>
<member>Magnus Hagander</member>
<member>Maja Zaloznik</member>
<member>Marcel Hofstetter</member>
<member>Marina Polyakova</member>
<member>Mark Dilger</member>
<member>Marko Tiikkaja</member>
<member>Markus Winand</member>
<member>Martijn van Oosterhout</member>
<member>Martin Jurca</member>
<member>Martin Kalcher</member>
<member>Mary Xu</member>
<member>Masahiko Sawada</member>
<member>Masahiro Ikeda</member>
<member>Masao Fujii</member>
<member>Mason Sharp</member>
<member>Matheus Alcantara</member>
<member>Mats Kindahl</member>
<member>Matthias van de Meent</member>
<member>Matthijs van der Vleuten</member>
<member>Maxim Orlov</member>
<member>Maxim Yablokov</member>
<member>Mehmet Emin Karakas</member>
<member>Melanie Plageman</member>
<member>Melih Mutlu</member>
<member>Micah Gate</member>
<member>Michael Banck</member>
<member>Michael Paquier</member>
<member>Michail Nikolaev</member>
<member>Michel Pelletier</member>
<member>Mike Oh</member>
<member>Mikhail Gribkov</member>
<member>Mingli Zhang</member>
<member>Miroslav Bendik</member>
<member>Mitsuru Hinata</member>
<member>Myo Wai Thant</member>
<member>Naeem Akhter</member>
<member>Naoki Okano</member>
<member>Nathan Bossart</member>
<member>Nazir Bilal Yavuz</member>
<member>Neha Sharma</member>
<member>Nick Babadzhanian</member>
<member>Nicola Contu</member>
<member>Nikhil Shetty</member>
<member>Nikita Glukhov</member>
<member>Nikolay Samokhvalov</member>
<member>Nikolay Shaplov</member>
<member>Nishant Sharma</member>
<member>Nitin Jadhav</member>
<member>Noah Misch</member>
<member>Noboru Saito</member>
<member>Noriyoshi Shinoda</member>
<member>Nuko Yokohama</member>
<member>Oleg Bartunov</member>
<member>Oleg Tselebrovskiy</member>
<member>Olly Betts</member>
<member>Onder Kalaci</member>
<member>Onur Tirtir</member>
<member>Pablo Federico</member>
<member>Palle Girgensohn</member>
<member>Paul Guo</member>
<member>Paul Jungwirth</member>
<member>Paul Ramsey</member>
<member>Pavel Borisov</member>
<member>Pavel Kulakov</member>
<member>Pavel Luzanov</member>
<member>Pavel Stehule</member>
<member>Peifeng Qiu</member>
<member>Peter Eisentraut</member>
<member>Peter Geoghegan</member>
<member>Peter Smith</member>
<member>Phil Florent</member>
<member>Philippe Godfrin</member>
<member>Platon Pronko</member>
<member>Przemyslaw Sztoch</member>
<member>Rachel Heaton</member>
<member>Ranier Vilela</member>
<member>Regina Obe</member>
<member>Reid Thompson</member>
<member>Reiner Peterke</member>
<member>Richard Guo</member>
<member>Riivo Kolka</member>
<member>Rishu Bagga</member>
<member>Robert Haas</member>
<member>Robert Sjöblom</member>
<member>Robert Treat</member>
<member>Roberto Mello</member>
<member>Robins Tharakan</member>
<member>Roman Zharkov</member>
<member>Ronan Dunklau</member>
<member>Rushabh Lathia</member>
<member>Ryo Matsumura</member>
<member>Samay Sharma</member>
<member>Sami Imseih</member>
<member>Sandeep Thakkar</member>
<member>Sandro Santilli</member>
<member>Sebastien Flaesch</member>
<member>Sébastien Lardière</member>
<member>Sehrope Sarkuni</member>
<member>Sergey Belyashov</member>
<member>Sergey Pankov</member>
<member>Sergey Shinderuk</member>
<member>Shi Yu</member>
<member>Shinya Kato</member>
<member>Sho Kato</member>
<member>Shruthi Gowda</member>
<member>Shveta Mallik</member>
<member>Simon Riggs</member>
<member>Sindy Senorita</member>
<member>Sirisha Chamarthi</member>
<member>Sravan Kumar</member>
<member>Stéphane Tachoires</member>
<member>Stephen Frost</member>
<member>Steve Chavez</member>
<member>Stone Tickle</member>
<member>Sven Klemm</member>
<member>Takamichi Osumi</member>
<member>Takeshi Ideriha</member>
<member>Tatsuhiro Nakamori</member>
<member>Tatsuo Ishii</member>
<member>Ted Yu</member>
<member>Teja Mupparti</member>
<member>Tender Wang</member>
<member>Teodor Sigaev</member>
<member>Thiago Nunes</member>
<member>Thom Brown</member>
<member>Thomas Habets</member>
<member>Thomas Mc Kay</member>
<member>Thomas Munro</member>
<member>Tim Carey-Smith</member>
<member>Tim Field</member>
<member>Timo Stolz</member>
<member>Tom Lane</member>
<member>Tomas Vondra</member>
<member>Tor Erik Linnerud</member>
<member>Torsten Förtsch</member>
<member>Tristan Partin</member>
<member>Troy Frericks</member>
<member>Tushar Ahuja</member>
<member>Valerie Woolard</member>
<member>Vibhor Kumar</member>
<member>Victor Spirin</member>
<member>Victoria Shepard</member>
<member>Vignesh C</member>
<member>Vik Fearing</member>
<member>Vitaly Burovoy</member>
<member>Vitaly Davydov</member>
<member>Wang Wei</member>
<member>Wenjing Zeng</member>
<member>Whale Song</member>
<member>Will Mortensen</member>
<member>Wolfgang Walther</member>
<member>Xin Wen</member>
<member>Xing Guo</member>
<member>Xingwang Xu</member>
<member>XueJing Zhao</member>
<member>Yanliang Lei</member>
<member>Youmiu Mo</member>
<member>Yugo Nagata</member>
<member>Yura Sokolov</member>
<member>Yuta Katsuragi</member>
<member>Zhen Mingyang</member>
<member>Zheng Li</member>
<member>Zhihong Yu</member>
<member>Zhijie Hou</member>
<member>Zongliang Quan</member>
<member>Zuming Jiang</member>
</simplelist>
</sect2>
</sect1>
