<!-- 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>AS OF 2023-08-14, 2023-??-??</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 easier
      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 the ability to perform <command>LOCK
        TABLE</command> at various lock levels was bound to
        specific query-type permissions.  For example, <link
        linkend="sql-update"><command>UPDATE</command></link>
        could perform all lock levels except
        <literal>ACCESS SHARE</literal>, which required <link
        linkend="sql-select"><command>SELECT</command></link> permissions.
        Now <command>UPDATE</command> can issue all lock levels.  MORE?
       </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-grant"><literal>GRANT group_name TO
        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-logical-replication-mode"><varname>logical_replication_mode</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>
       permissions on all 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 &lt;name&gt; 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 <acronym>WAL</acronym>
       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>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>
