<!-- doc/src/sgml/release-18.sgml -->
<!-- See header comment in release.sgml about typical markup -->

 <sect1 id="release-18">
  <title>Release 18</title>

  <formalpara>
   <title>Release date:</title>
   <para>2025-??-??, CURRENT AS OF 2025-08-29</para>
  </formalpara>

  <sect2 id="release-18-highlights">
   <title>Overview</title>

   <para>
    <productname>PostgreSQL</productname> 18 contains many new features
    and enhancements, including:
   </para>

   <itemizedlist>

    <listitem>
     <para>
      (to be completed)
     </para>
    </listitem>
   </itemizedlist>

   <para>
    The above items and other new features of
    <productname>PostgreSQL</productname> 18 are explained in more detail
    in the sections below.
   </para>

  </sect2>

  <sect2  id="release-18-migration">

   <title>Migration to Version 18</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 18 contains a number of changes that may affect compatibility
    with previous releases.  Observe the following incompatibilities:
   </para>

   <itemizedlist>

<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2024-10-16 [04bec894a04] initdb: Change default to using data checksums.
-->

    <listitem>
    <para>
    Change <xref linkend="app-initdb"/> default to enable data checksums
    (Greg Sabino Mullane)
    <ulink url="&commit_baseurl;04bec894a04">&sect;</ulink>
    </para>

    <para>
    Checksums can be disabled with the
    new <application>initdb</application> option
    <option>--no-data-checksums</option>.  <xref linkend="pgupgrade"/>
    requires matching cluster checksum settings, so this new option can
    be useful to upgrade non-checksum old clusters.
    </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2025-01-16 [d7674c9fa] Seek zone abbreviations in the IANA data before timezone
-->

    <listitem>
    <para>
    Change time zone abbreviation handling (Tom Lane)
    <ulink url="&commit_baseurl;d7674c9fa">&sect;</ulink>
    </para>

    <para>
    The system will now favor the current session's time
    zone abbreviations before checking the server variable
    <xref linkend="guc-timezone-abbreviations"/>. Previously
    <varname>timezone_abbreviations</varname> was checked first.
    </para>
    </listitem>

<!--
Author: Nathan Bossart <nathan@postgresql.org>
2024-12-02 [db6a4a985] Deprecate MD5 passwords.
-->

    <listitem>
    <para>
    Deprecate <link linkend="auth-password">MD5 password</link>
    authentication (Nathan Bossart)
    <ulink url="&commit_baseurl;db6a4a985">&sect;</ulink>
    </para>

    <para>
    Support for MD5 passwords will be removed in a future major
    version release.  <xref linkend="sql-createrole"/> and <xref
    linkend="sql-alterrole"/> now emit deprecation warnings when
    setting MD5 passwords.  These warnings can be disabled by setting
    the <xref linkend="guc-md5-password-warnings"/> parameter to
    <literal>off</literal>.
    </para>
    </listitem>

<!--
Author: David Rowley <drowley@postgresql.org>
2024-09-24 [62ddf7ee9] Add ONLY support for VACUUM and ANALYZE
-->

    <listitem>
    <para>
    Change <xref linkend="sql-vacuum"/> and <xref linkend="sql-analyze"/>
    to process the inheritance children of a parent (Michael Harris)
    <ulink url="&commit_baseurl;62ddf7ee9">&sect;</ulink>
    </para>

    <para>
    The previous behavior can be performed by using the new
    <literal>ONLY</literal> option.
    </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2024-09-30 [770233748] Do not treat \. as an EOF marker in CSV mode for COPY IN
Author: Tom Lane <tgl@sss.pgh.pa.us>
2024-10-01 [da8a4c166] Reject a copy EOF marker that has data ahead of it on th
-->

    <listitem>
    <para>
    Prevent <link linkend="sql-copy"><command>COPY FROM</command></link>
    from treating <literal>\.</literal> as an end-of-file marker when
    reading <acronym>CSV</acronym> files (Daniel Vérité, Tom Lane)
    <ulink url="&commit_baseurl;770233748">&sect;</ulink>
    <ulink url="&commit_baseurl;da8a4c166">&sect;</ulink>
    </para>

    <para>
    <xref linkend="app-psql"/> will still treat
    <literal>\.</literal> as an end-of-file marker when reading
    <acronym>CSV</acronym> files from <literal>STDIN</literal>.
    Older <application>psql</application> clients connecting to
    <productname>PostgreSQL</productname> 18 servers might experience <link
    linkend="app-psql-meta-commands-copy"><literal>\copy</literal></link>
    problems.  This release also enforces that <literal>\.</literal>
    must appear alone on a line.
    </para>
    </listitem>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2024-10-03 [e2bab2d79] Remove support for unlogged on partitioned tables
-->

    <listitem>
    <para>
    Disallow unlogged partitioned tables (Michael Paquier)
    <ulink url="&commit_baseurl;e2bab2d79">&sect;</ulink>
    </para>

    <para>
    Previously <link linkend="sql-altertable"><command>ALTER TABLE SET
    [UN]LOGGED</command></link> did nothing, and the creation of an
    unlogged partitioned table did not cause its children to be unlogged.
    </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2025-01-23 [01463e1cc] Ensure that AFTER triggers run as the instigating user.
-->

    <listitem>
    <para>
    Execute <literal>AFTER</literal> <link
    linkend="triggers">triggers</link> as the role that was active when
    trigger events were queued (Laurenz Albe)
    <ulink url="&commit_baseurl;01463e1cc">&sect;</ulink>
    </para>

    <para>
    Previously such triggers were run as the role that was active at
    trigger execution time (e.g., at <xref linkend="sql-commit"/>).
    This is significant for cases where the role is changed between queue
    time and transaction commit.
    </para>
    </listitem>

<!--
Author: Fujii Masao <fujii@postgresql.org>
2024-09-12 [fefa76f70] Remove old RULE privilege completely.
-->

    <listitem>
    <para>
    Remove non-functional support for rule privileges in <xref
    linkend="sql-grant"/>/<xref linkend="sql-revoke"/> (Fujii Masao)
    <ulink url="&commit_baseurl;fefa76f70">&sect;</ulink>
    </para>

    <para>
    These have been non-functional since
    <productname>PostgreSQL</productname> 8.2.
    </para>
    </listitem>

<!--
Author: David Rowley <drowley@postgresql.org>
2024-08-12 [f0d112759] Remove "parent" column from pg_backend_memory_contexts
-->

    <listitem>
    <para>
    Remove column <link
    linkend="view-pg-backend-memory-contexts"><structname>pg_backend_memory_contexts</structname></link>.<structfield>parent</structfield>
    (Melih Mutlu)
    <ulink url="&commit_baseurl;f0d112759">&sect;</ulink>
    </para>

    <para>
    This is no longer needed since
    <structname>pg_backend_memory_contexts</structname>.<structfield>path</structfield>
    was added.
    </para>
    </listitem>

<!--
Author: David Rowley <drowley@postgresql.org>
2024-07-25 [32d3ed816] Add path column to pg_backend_memory_contexts view
Author: David Rowley <drowley@postgresql.org>
2025-04-18 [d9e03864b] Make levels 1-based in
    pg_log_backend_memory_contexts()
Author: Fujii Masao <fujii@postgresql.org>
2025-04-21 [706cbed35] doc: Fix memory context level in pg_log_backend_memory_c
-->

    <listitem>
    <para>
    Change
    <structname>pg_backend_memory_contexts</structname>.<structfield>level</structfield>
    and <link
    linkend="functions-admin-signal-table"><function>pg_log_backend_memory_contexts()</function></link>
    to be one-based (Melih Mutlu, Atsushi Torikoshi, David Rowley,
    Fujii Masao)
    <ulink url="&commit_baseurl;32d3ed816">&sect;</ulink>
    <ulink url="&commit_baseurl;d9e03864b">&sect;</ulink>
    <ulink url="&commit_baseurl;706cbed35">&sect;</ulink>
    </para>

    <para>
    These were previously zero-based.
    </para>
    </listitem>

<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2024-12-17 [fb1a18810f0] Remove ts_locale.c's lowerstr()
-->

    <listitem>
    <para>
    Change <link linkend="textsearch">full text search</link> to use the
    default collation provider of the cluster to read configuration files
    and dictionaries, rather than always using libc (Peter Eisentraut)
    <ulink url="&commit_baseurl;fb1a18810f0">&sect;</ulink>
    </para>

    <para>
    Clusters that default to non-libc collation providers (e.g., ICU,
    builtin) that behave differently than libc for characters processed
    by LC_CTYPE could observe changes in behavior of some full-text
    search functions, as well as the <xref linkend="pgtrgm"/> extension.
    When upgrading such clusters using <xref linkend="pgupgrade"/>, it
    is recommended to reindex all indexes related to full-text search
    and <application>pg_trgm</application> after the upgrade.
    </para>
    </listitem>

   </itemizedlist>

  </sect2>

  <sect2 id="release-18-changes">
   <title>Changes</title>

    <para>
     Below you will find a detailed account of the changes between
    <productname>PostgreSQL</productname> 18 and the previous major
    release.
    </para>

   <sect3 id="release-18-server">
    <title>Server</title>

    <sect4 id="release-18-optimizer">
     <title>Optimizer</title>

     <itemizedlist>

<!--
Author: Alexander Korotkov <akorotkov@postgresql.org>
2025-02-17 [fc069a3a6] Implement Self-Join Elimination
-->

      <listitem>
      <para>
      Automatically remove some unnecessary table self-joins (Andrey
      Lepikhov, Alexander Kuzmenkov, Alexander Korotkov, Alena Rybakina)
      <ulink url="&commit_baseurl;fc069a3a6">&sect;</ulink>
      </para>

      <para>
      This optimization can be disabled using server variable <xref
      linkend="guc-enable-self-join-elimination"/>.
      </para>
      </listitem>

<!--
Author: Alexander Korotkov <akorotkov@postgresql.org>
2025-04-04 [c0962a113] Convert 'x IN (VALUES ...)' to 'x = ANY ...' then approp
-->

      <listitem>
      <para>
      Convert some <link
      linkend="functions-comparisons-in-scalar"><literal>IN (VALUES
      ...)</literal></link> to <literal>x = ANY ...</literal> for better
      optimizer statistics (Alena Rybakina, Andrei Lepikhov)
      <ulink url="&commit_baseurl;c0962a113">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Alexander Korotkov <akorotkov@postgresql.org>
2024-11-24 [ae4569161] Teach bitmap path generation about transforming OR-claus
-->

      <listitem>
      <para>
      Allow transforming <link
      linkend="functions-logical"><literal>OR</literal></link>-clauses
      to arrays for faster index processing (Alexander Korotkov, Andrey
      Lepikhov)
      <ulink url="&commit_baseurl;ae4569161">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2024-09-10 [52c707483] Use a hash table to de-duplicate column names in ruleuti
Author: Tom Lane <tgl@sss.pgh.pa.us>
2024-12-19 [276279295] Convert SetOp to read its inputs as outerPlan and innerP
Author: Tom Lane <tgl@sss.pgh.pa.us>
2024-12-19 [8d96f57d5] Improve planner's handling of SetOp plans.
Author: David Rowley <drowley@postgresql.org>
2024-09-05 [908a96861] Optimize WindowAgg's use of tuplestores
-->

      <listitem>
      <para>
      Speed up the processing of <link
      linkend="sql-intersect"><literal>INTERSECT</literal></link>,
      <link linkend="sql-except"><literal>EXCEPT</literal></link>, <link
      linkend="tutorial-window">window aggregates</link>, and <link
      linkend="sql-createview">view column aliases</link> (Tom Lane,
      David Rowley)
      <ulink url="&commit_baseurl;52c707483">&sect;</ulink>
      <ulink url="&commit_baseurl;276279295">&sect;</ulink>
      <ulink url="&commit_baseurl;8d96f57d5">&sect;</ulink>
      <ulink url="&commit_baseurl;908a96861">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Richard Guo <rguo@postgresql.org>
2024-11-26 [a8ccf4e93] Reordering DISTINCT keys to match input path's pathkeys
-->

      <listitem>
      <para>
      Allow the keys of <link linkend="sql-distinct"><command>SELECT
      DISTINCT</command></link> to be internally reordered to avoid sorting
      (Richard Guo)
      <ulink url="&commit_baseurl;a8ccf4e93">&sect;</ulink>
      </para>

      <para>
      This optimization can be disabled using <xref
      linkend="guc-enable-distinct-reordering"/>.
      </para>
      </listitem>

<!--
Author: David Rowley <drowley@postgresql.org>
2024-12-12 [bd10ec529] Detect redundant GROUP BY columns using UNIQUE indexes
-->

      <listitem>
      <para>
      Ignore <link linkend="sql-groupby"><literal>GROUP BY</literal></link>
      columns that are functionally dependent on other columns (Zhang
      Mingli, Jian He, David Rowley)
      <ulink url="&commit_baseurl;bd10ec529">&sect;</ulink>
      </para>

      <para>
      If a <literal>GROUP BY</literal> clause includes all columns of
      a unique index, as well as other columns of the same table, those
      other columns are redundant and can be dropped from the grouping.
      This was already true for non-deferred primary keys.
      </para>
      </listitem>

<!--
Author: Richard Guo <rguo@postgresql.org>
2024-10-09 [67a54b9e8] Allow pushdown of HAVING clauses with grouping sets
Author: Richard Guo <rguo@postgresql.org>
2024-09-10 [247dea89f] Introduce an RTE for the grouping step
Author: Richard Guo <rguo@postgresql.org>
2024-09-10 [f5050f795] Mark expressions nullable by grouping sets
Author: Richard Guo <rguo@postgresql.org>
2025-03-13 [cc5d98525] Fix incorrect handling of subquery pullup
-->

      <listitem>
      <para>
      Allow some <link
      linkend="sql-having"><literal>HAVING</literal></link> clauses
      on <link linkend="queries-grouping-sets"><literal>GROUPING
      SETS</literal></link> to be pushed to <link
      linkend="sql-where"><literal>WHERE</literal></link> clauses
      (Richard Guo)
      <ulink url="&commit_baseurl;67a54b9e8">&sect;</ulink>
      <ulink url="&commit_baseurl;247dea89f">&sect;</ulink>
      <ulink url="&commit_baseurl;f5050f795">&sect;</ulink>
      <ulink url="&commit_baseurl;cc5d98525">&sect;</ulink>
      </para>

      <para>
      This allows earlier row filtering.  This release also fixes some
      <literal>GROUPING SETS</literal> queries that used to return
      incorrect results.
      </para>
      </listitem>

<!--
Author: David Rowley <drowley@postgresql.org>
2024-07-09 [036bdcec9] Teach planner how to estimate rows for timestamp generat
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
2024-12-02 [97173536e] Add a planner support function for numeric generate_seri
-->

      <listitem>
      <para>
      Improve row estimates for <link
      linkend="functions-srf-series"><function>generate_series()</function></link>
      using <link linkend="datatype-numeric"><type>numeric</type></link>
      and <link linkend="datatype-datetime"><type>timestamp</type></link>
      values (David Rowley, Song Jinzhou)
      <ulink url="&commit_baseurl;036bdcec9">&sect;</ulink>
      <ulink url="&commit_baseurl;97173536e">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Richard Guo <rguo@postgresql.org>
2024-07-05 [aa86129e1] Support "Right Semi Join" plan shapes
-->

      <listitem>
      <para>
      Allow the optimizer to use <literal>Right Semi Join</literal> plans
      (Richard Guo)
      <ulink url="&commit_baseurl;aa86129e1">&sect;</ulink>
      </para>

      <para>
      Semi-joins are used when needing to find if there is at least
      one match.
      </para>
      </listitem>

<!--
Author: Richard Guo <rguo@postgresql.org>
2024-10-09 [828e94c9d] Consider explicit incremental sort for mergejoins
-->

      <listitem>
      <para>
      Allow merge joins to use <link
      linkend="guc-enable-incremental-sort">incremental sorts</link>
      (Richard Guo)
      <ulink url="&commit_baseurl;828e94c9d">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Amit Langote <amitlan@postgresql.org>
2025-04-04 [88f55bc97] Make derived clause lookup in EquivalenceClass more effi
Author: David Rowley <drowley@postgresql.org>
2025-04-08 [d69d45a5a] Speedup child EquivalenceMember lookup in planner
-->

      <listitem>
      <para>
      Improve the efficiency of planning queries accessing many partitions
      (Ashutosh Bapat, Yuya Watari, David Rowley)
      <ulink url="&commit_baseurl;88f55bc97">&sect;</ulink>
      <ulink url="&commit_baseurl;d69d45a5a">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Richard Guo <rguo@postgresql.org>
2024-07-30 [9b282a935] Fix partitionwise join with partially-redundant join cla
Author: Richard Guo <rguo@postgresql.org>
2024-07-29 [513f4472a] Reduce memory used by partitionwise joins
-->

      <listitem>
      <para>
      Allow <link linkend="guc-enable-partitionwise-join">partitionwise
      joins</link> in more cases, and reduce its memory usage (Richard Guo,
      Tom Lane, Ashutosh Bapat)
      <ulink url="&commit_baseurl;9b282a935">&sect;</ulink>
      <ulink url="&commit_baseurl;513f4472a">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Alexander Korotkov <akorotkov@postgresql.org>
2025-03-10 [fae535da0] Teach Append to consider tuple_fraction when accumulatin
-->

      <listitem>
      <para>
      Improve cost estimates of partition queries (Nikita Malakhov,
      Andrei Lepikhov)
      <ulink url="&commit_baseurl;fae535da0">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2025-04-02 [0dca5d68d] Change SQL-language functions to use the plan cache.
Author: Tom Lane <tgl@sss.pgh.pa.us>
2025-04-17 [09b07c295] Minor performance improvement for SQL-language functions
-->

      <listitem>
      <para>
      Improve <link linkend="xfunc-sql"><acronym>SQL</acronym>-language
      function</link> plan caching (Alexander Pyhalov, Tom Lane)
      <ulink url="&commit_baseurl;0dca5d68d">&sect;</ulink>
      <ulink url="&commit_baseurl;09b07c295">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Robert Haas <rhaas@postgresql.org>
2024-08-21 [e22253467] Treat number of disabled nodes in a path as a separate c
-->

      <listitem>
      <para>
      Improve handling of disabled optimizer features (Robert Haas)
      <ulink url="&commit_baseurl;e22253467">&sect;</ulink>
      </para>
      </listitem>

     </itemizedlist>

    </sect4>

    <sect4 id="release-18-indexes">
     <title>Indexes</title>

     <itemizedlist>

<!--
Author: Peter Geoghegan <pg@bowt.ie>
2025-04-04 [92fe23d93] Add nbtree skip scan optimization.
Author: Peter Geoghegan <pg@bowt.ie>
2025-04-04 [8a510275d] Further optimize nbtree search scan key comparisons.
-->

      <listitem>
      <para>
      Allow skip scans of <link linkend="xfunc-sql">btree</link> indexes
      (Peter Geoghegan)
      <ulink url="&commit_baseurl;92fe23d93">&sect;</ulink>
      <ulink url="&commit_baseurl;8a510275d">&sect;</ulink>
      </para>

      <para>
      This allows multi-column btree indexes to be used by queries that
      only equality-reference the second or later indexed columns.
      </para>
      </listitem>

<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2025-03-18 [f278e1fe3] Allow non-btree unique indexes for partition keys
Author: Peter Eisentraut <peter@eisentraut.org>
2025-03-18 [9d6db8bec] Allow non-btree unique indexes for matviews
-->

      <listitem>
      <para>
      Allow non-btree unique indexes to be used as partition keys and in
      materialized views (Mark Dilger)
      <ulink url="&commit_baseurl;f278e1fe3">&sect;</ulink>
      <ulink url="&commit_baseurl;9d6db8bec">&sect;</ulink>
      </para>

      <para>
      The index type must still support equality.
      </para>
      </listitem>

<!--
Author: Tomas Vondra <tomas.vondra@postgresql.org>
2025-03-03 [8492feb98] Allow parallel CREATE INDEX for GIN indexes
-->

      <listitem>
      <para>
      Allow <link linkend="gin"><literal>GIN</literal></link> indexes to
      be created in parallel (Tomas Vondra, Matthias van de Meent)
      <ulink url="&commit_baseurl;8492feb98">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
2025-04-02 [e9e7b6604] Add GiST and btree sortsupport routines for range types
-->

      <listitem>
      <para>
      Allow values to be sorted to speed range-type <link
      linkend="gist">GiST</link> and <link linkend="btree">btree</link>
      index builds (Bernd Helmle)
      <ulink url="&commit_baseurl;e9e7b6604">&sect;</ulink>
      </para>
      </listitem>

     </itemizedlist>

    </sect4>

    <sect4 id="release-18-performance">
     <title>General Performance</title>

     <itemizedlist>

<!--
Author: Andres Freund <andres@anarazel.de>
2025-03-17 [02844012b] aio: Basic subsystem initialization
Author: Andres Freund <andres@anarazel.de>
2025-03-17 [da7226993] aio: Add core asynchronous I/O infrastructure
Author: Andres Freund <andres@anarazel.de>
2025-03-18 [55b454d0e] aio: Infrastructure for io_method=worker
Author: Andres Freund <andres@anarazel.de>
2025-03-18 [247ce06b8] aio: Add io_method=worker
Author: Thomas Munro <tmunro@postgresql.org>
2025-03-19 [10f664684] Introduce io_max_combine_limit.
Author: Thomas Munro <tmunro@postgresql.org>
2025-03-19 [06fb5612c] Increase io_combine_limit range to 1MB.
Author: Andres Freund <andres@anarazel.de>
2025-03-26 [c325a7633] aio: Add io_method=io_uring
Author: Andres Freund <andres@anarazel.de>
2025-03-29 [50cb7505b] aio: Implement support for reads in smgr/md/fd
Author: Andres Freund <andres@anarazel.de>
2025-03-30 [047cba7fa] bufmgr: Implement AIO read support
Author: Andres Freund <andres@anarazel.de>
2025-03-30 [12ce89fd0] bufmgr: Use AIO in StartReadBuffers()
Author: Andres Freund <andres@anarazel.de>
2025-03-30 [2a5e709e7] Enable IO concurrency on all systems
-->

      <listitem>
      <para>
      Add an asynchronous I/O subsystem (Andres Freund, Thomas Munro,
      Nazir Bilal Yavuz, Melanie Plageman)
      <ulink url="&commit_baseurl;02844012b">&sect;</ulink>
      <ulink url="&commit_baseurl;da7226993">&sect;</ulink>
      <ulink url="&commit_baseurl;55b454d0e">&sect;</ulink>
      <ulink url="&commit_baseurl;247ce06b8">&sect;</ulink>
      <ulink url="&commit_baseurl;10f664684">&sect;</ulink>
      <ulink url="&commit_baseurl;06fb5612c">&sect;</ulink>
      <ulink url="&commit_baseurl;c325a7633">&sect;</ulink>
      <ulink url="&commit_baseurl;50cb7505b">&sect;</ulink>
      <ulink url="&commit_baseurl;047cba7fa">&sect;</ulink>
      <ulink url="&commit_baseurl;12ce89fd0">&sect;</ulink>
      <ulink url="&commit_baseurl;2a5e709e7">&sect;</ulink>
      </para>

      <para>
      This feature allows backends to queue multiple read requests,
      which allows for more efficient sequential scans, bitmap
      heap scans, vacuums, etc.  This is enabled by server
      variable <xref linkend="guc-io-method"/>, with server
      variables <xref linkend="guc-io-combine-limit"/> and <xref
      linkend="guc-io-max-combine-limit"/> added to control it.
      This also enables <xref linkend="guc-effective-io-concurrency"/>
      and <xref linkend="guc-maintenance-io-concurrency"/>
      values greater than zero for systems without
      <function>fadvise()</function> support.  The new system view <link
      linkend="view-pg-aios"><structname>pg_aios</structname></link>
      shows the file handles being used for asynchronous I/O.
      </para>
      </listitem>

<!--
Author: Tomas Vondra <tomas.vondra@postgresql.org>
2024-09-21 [c4d5cb71d] Increase the number of fast-path lock slots
-->

      <listitem>
      <para>
      Improve the locking performance of queries that access many relations
      (Tomas Vondra)
      <ulink url="&commit_baseurl;c4d5cb71d">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: David Rowley <drowley@postgresql.org>
2024-08-20 [adf97c156] Speed up Hash Join by making ExprStates support hashing
Author: David Rowley <drowley@postgresql.org>
2024-12-11 [0f5738202] Use ExprStates for hashing in GROUP BY and SubPlans
Author: Jeff Davis <jdavis@postgresql.org>
2025-03-24 [4d143509c] Create accessor functions for TupleHashEntry.
Author: Jeff Davis <jdavis@postgresql.org>
2025-03-24 [a0942f441] Add ExecCopySlotMinimalTupleExtra().
Author: Jeff Davis <jdavis@postgresql.org>
2025-03-24 [626df47ad] Remove 'additional' pointer from TupleHashEntryData.
-->

      <listitem>
      <para>
      Improve the performance and reduce memory usage of hash joins and
      <link linkend="sql-groupby"><literal>GROUP BY</literal></link>
      (David Rowley, Jeff Davis)
      <ulink url="&commit_baseurl;adf97c156">&sect;</ulink>
      <ulink url="&commit_baseurl;0f5738202">&sect;</ulink>
      <ulink url="&commit_baseurl;4d143509c">&sect;</ulink>
      <ulink url="&commit_baseurl;a0942f441">&sect;</ulink>
      <ulink url="&commit_baseurl;626df47ad">&sect;</ulink>
      </para>

      <para>
      This also improves hash set operations used by <link
      linkend="sql-except"><literal>EXCEPT</literal></link>, and hash
      lookups of subplan values.
      </para>
      </listitem>

<!--
Author: Melanie Plageman <melanieplageman@gmail.com>
2025-02-11 [052026c9b] Eagerly scan all-visible pages to amortize aggressive va
Author: Melanie Plageman <melanieplageman@gmail.com>
2025-03-03 [06eae9e62] Trigger more frequent autovacuums with relallfrozen
-->

      <listitem>
      <para>
      Allow normal vacuums to freeze some pages, even though they are
      all-visible (Melanie Plageman)
      <ulink url="&commit_baseurl;052026c9b">&sect;</ulink>
      <ulink url="&commit_baseurl;06eae9e62">&sect;</ulink>
      </para>

      <para>
      This reduces the overhead of later full-relation
      freezing.  The aggressiveness of this can be
      controlled by server variable and per-table setting <xref
      linkend="guc-vacuum-max-eager-freeze-failure-rate"/>.  Previously
      vacuum never processed all-visible pages until freezing was required.
      </para>
      </listitem>

<!--
Author: Nathan Bossart <nathan@postgresql.org>
2025-03-20 [0164a0f9e] Add vacuum_truncate configuration parameter.
-->

      <listitem>
      <para>
      Add server variable <xref linkend="guc-vacuum-truncate"/> to control
      file truncation during <xref linkend="sql-vacuum"/> (Nathan Bossart,
      Gurjeet Singh)
      <ulink url="&commit_baseurl;0164a0f9e">&sect;</ulink>
      </para>

      <para>
      A storage-level parameter with the same name and behavior already
      existed.
      </para>
      </listitem>

<!--
Author: Melanie Plageman <melanieplageman@gmail.com>
2025-03-12 [ff79b5b2a] Increase default effective_io_concurrency to 16
Author: Melanie Plageman <melanieplageman@gmail.com>
2025-03-18 [cc6be07eb] Increase default maintenance_io_concurrency to 16
-->

      <listitem>
      <para>
      Increase server variables <xref
      linkend="guc-effective-io-concurrency"/>'s and <xref
      linkend="guc-maintenance-io-concurrency"/>'s default values to 16
      (Melanie Plageman)
      <ulink url="&commit_baseurl;ff79b5b2a">&sect;</ulink>
      <ulink url="&commit_baseurl;cc6be07eb">&sect;</ulink>
      </para>

      <para>
      This more accurately reflects modern hardware.
      </para>
      </listitem>

     </itemizedlist>

    </sect4>

    <sect4 id="release-18-monitoring">
     <title>Monitoring</title>

     <itemizedlist>

<!--
Author: Melanie Plageman <melanieplageman@gmail.com>
2025-03-12 [9219093ca] Modularize log_connections output
-->

      <listitem>
      <para>
      Increase the logging granularity of server variable <xref
      linkend="guc-log-connections"/> (Melanie Plageman)
      <ulink url="&commit_baseurl;9219093ca">&sect;</ulink>
      </para>

      <para>
      This server variable was previously only boolean, which is still
      supported.
      </para>
      </listitem>

<!--
Author: Melanie Plageman <melanieplageman@gmail.com>
2025-03-12 [18cd15e70] Add connection establishment duration logging
-->

      <listitem>
      <para>
      Add <varname>log_connections</varname> option to report the duration
      of connection stages (Melanie Plageman)
      <ulink url="&commit_baseurl;18cd15e70">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2025-04-07 [3516ea768] Add local-address escape "%L" to log_line_prefix.
-->

      <listitem>
      <para>
      Add <xref linkend="guc-log-line-prefix"/> escape
      <literal>%L</literal> to output the client <acronym>IP</acronym>
      address (Greg Sabino Mullane)
      <ulink url="&commit_baseurl;3516ea768">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Fujii Masao <fujii@postgresql.org>
2025-03-14 [6d376c3b0] Add GUC option to log lock acquisition failures.
Author: Fujii Masao <fujii@postgresql.org>
2025-06-03 [73bdcfab3] Rename log_lock_failure GUC to log_lock_failures for con
-->

      <listitem>
      <para>
      Add server variable <xref linkend="guc-log-lock-failures"/> to log
      lock acquisition failures (Yuki Seino, Fujii Masao)
      <ulink url="&commit_baseurl;6d376c3b0">&sect;</ulink>
      <ulink url="&commit_baseurl;73bdcfab3">&sect;</ulink>
      </para>

      <para>
      Specifically it reports <link
      linkend="sql-for-update-share"><command>SELECT
      ... NOWAIT</command></link> lock failures.
      </para>
      </listitem>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2025-01-28 [30a6ed0ce] Track per-relation cumulative time spent in [auto]vacuum
-->

      <listitem>
      <para>
      Modify <link
      linkend="monitoring-pg-stat-all-tables-view"><structname>pg_stat_all_tables</structname></link>
      and its variants to report the time spent in <xref
      linkend="sql-vacuum"/>, <xref linkend="sql-analyze"/>, and their
      <link linkend="autovacuum">automatic</link> variants (Sami Imseih)
      <ulink url="&commit_baseurl;30a6ed0ce">&sect;</ulink>
      </para>

      <para>
      The new columns are <structfield>total_vacuum_time</structfield>,
      <structfield>total_autovacuum_time</structfield>,
      <structfield>total_analyze_time</structfield>, and
      <structfield>total_autoanalyze_time</structfield>.
      </para>
      </listitem>

<!--
Author: Nathan Bossart <nathan@postgresql.org>
2025-02-11 [bb8dff999] Add cost-based vacuum delay time to progress views.
Author: Nathan Bossart <nathan@postgresql.org>
2025-02-14 [7720082ae] Add delay time to VACUUM/ANALYZE (VERBOSE) and autovacuu
-->

      <listitem>
      <para>
      Add delay time reporting to <xref linkend="sql-vacuum"/> and <xref
      linkend="sql-analyze"/> (Bertrand Drouvot, Nathan Bossart)
      <ulink url="&commit_baseurl;bb8dff999">&sect;</ulink>
      <ulink url="&commit_baseurl;7720082ae">&sect;</ulink>
      </para>

      <para>
      This information appears in the server log, the system views <link
      linkend="vacuum-progress-reporting"><structname>pg_stat_progress_vacuum</structname></link>
      and <link
      linkend="pg-stat-progress-analyze-view"><structname>pg_stat_progress_analyze</structname></link>,
      and the output of <xref linkend="sql-vacuum"/> and <xref
      linkend="sql-analyze"/> when in <literal>VERBOSE</literal>
      mode; tracking must be enabled with the server variable <xref
      linkend="guc-track-cost-delay-timing"/>.
      </para>
      </listitem>

<!--
Author: Masahiko Sawada <msawada@postgresql.org>
2024-08-13 [4c1b4cdb8] Add resource statistics reporting to ANALYZE VERBOSE.
Author: Masahiko Sawada <msawada@postgresql.org>
2024-09-09 [bb7775234] Add WAL usage reporting to ANALYZE VERBOSE output.
-->

      <listitem>
      <para>
      Add <acronym>WAL</acronym>, <acronym>CPU</acronym>, and average
      read statistics output to <command>ANALYZE VERBOSE</command>
      (Anthonin Bonnefoy)
      <ulink url="&commit_baseurl;4c1b4cdb8">&sect;</ulink>
      <ulink url="&commit_baseurl;bb7775234">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2025-02-17 [6a8a7ce47] Add information about WAL buffers full to VACUUM/ANALYZE
-->

      <listitem>
      <para>
      Add full <acronym>WAL</acronym> buffer count to
      <command>VACUUM</command>/<command>ANALYZE (VERBOSE)</command>
      and autovacuum log output (Bertrand Drouvot)
      <ulink url="&commit_baseurl;6a8a7ce47">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2024-12-19 [9aea73fc6] Add backend-level statistics to pgstats
Author: Michael Paquier <michael@paquier.xyz>
2025-03-03 [3f1db99bf] Handle auxiliary processes in SQL functions of backend s
-->

      <listitem>
      <para>
      Add per-backend I/O statistics reporting (Bertrand Drouvot)
      <ulink url="&commit_baseurl;9aea73fc6">&sect;</ulink>
      <ulink url="&commit_baseurl;3f1db99bf">&sect;</ulink>
      </para>

      <para>
      The statistics are accessed via <link
      linkend="pg-stat-get-backend-io"><function>pg_stat_get_backend_io()</function></link>.
      Per-backend I/O statistics can be cleared via <link
      linkend="monitoring-stats-funcs-table"><function>pg_stat_reset_backend_stats()</function></link>.
      </para>
      </listitem>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2025-01-14 [f92c854cf] Make pg_stat_io count IOs as bytes instead of blocks for
-->

      <listitem>
      <para>
      Add <link
      linkend="monitoring-pg-stat-io-view"><structname>pg_stat_io</structname></link>
      columns to report I/O activity in bytes (Nazir Bilal Yavuz)
      <ulink url="&commit_baseurl;f92c854cf">&sect;</ulink>
      </para>

      <para>
      The new columns are <structfield>read_bytes</structfield>,
      <structfield>write_bytes</structfield>, and
      <structfield>extend_bytes</structfield>.  The
      <structfield>op_bytes</structfield> column, which always equaled
      <link linkend="guc-block-size"><varname>BLCKSZ</varname></link>,
      has been removed.
      </para>
      </listitem>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2025-02-04 [a051e71e2] Add data for WAL in pg_stat_io and backend statistics
Author: Michael Paquier <michael@paquier.xyz>
2025-02-20 [4538bd3f1] doc: Add details about object "wal" in pg_stat_io
Author: Michael Paquier <michael@paquier.xyz>
2025-03-06 [7f7f324eb] Add more monitoring data for WAL writes in the WAL recei
-->

      <listitem>
      <para>
      Add <acronym>WAL</acronym> I/O activity rows to
      <structname>pg_stat_io</structname> (Nazir Bilal Yavuz, Bertrand
      Drouvot, Michael Paquier)
      <ulink url="&commit_baseurl;a051e71e2">&sect;</ulink>
      <ulink url="&commit_baseurl;4538bd3f1">&sect;</ulink>
      <ulink url="&commit_baseurl;7f7f324eb">&sect;</ulink>
      </para>

      <para>
      This includes <acronym>WAL</acronym> receiver activity and a wait
      event for such writes.
      </para>

      </listitem>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2025-02-26 [6c349d83b] Re-add GUC track_wal_io_timing
-->

      <listitem>
      <para>
      Change server variable <xref linkend="guc-track-wal-io-timing"/>
      to control tracking <acronym>WAL</acronym> timing
      in <structname>pg_stat_io</structname> instead of <link
      linkend="pg-stat-wal-view"><structname>pg_stat_wal</structname></link>
      (Bertrand Drouvot)
      <ulink url="&commit_baseurl;6c349d83b">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2025-02-24 [2421e9a51] Remove read/sync fields from pg_stat_wal and GUC track_w
Author: Michael Paquier <michael@paquier.xyz>
2025-02-26 [6c349d83b] Re-add GUC track_wal_io_timing
-->

      <listitem>
      <para>
      Remove read/sync columns from <structname>pg_stat_wal</structname>
      (Bertrand Drouvot)
      <ulink url="&commit_baseurl;2421e9a51">&sect;</ulink>
      <ulink url="&commit_baseurl;6c349d83b">&sect;</ulink>
      </para>

      <para>
      This removes columns <structfield>wal_write</structfield>,
      <structfield>wal_sync</structfield>,
      <structfield>wal_write_time</structfield>, and
      <structfield>wal_sync_time</structfield>.
      </para>
      </listitem>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2025-03-11 [76def4cdd] Add WAL data to backend statistics
-->

      <listitem>
      <para>
      Add function <link
      linkend="pg-stat-get-backend-wal"><function>pg_stat_get_backend_wal()</function></link>
      to return per-backend <acronym>WAL</acronym> statistics (Bertrand
      Drouvot)
      <ulink url="&commit_baseurl;76def4cdd">&sect;</ulink>
      </para>

      <para>
      Per-backend <acronym>WAL</acronym>
      statistics can be cleared via <link
      linkend="monitoring-stats-funcs-table"><function>pg_stat_reset_backend_stats()</function></link>.
      </para>
      </listitem>

<!--
Author: Nathan Bossart <nathan@postgresql.org>
2024-10-11 [4e1fad378] Add pg_ls_summariesdir().
-->

      <listitem>
      <para>
      Add function <link
      linkend="functions-admin-genfile-table"><function>pg_ls_summariesdir()</function></link>
      to specifically list the contents of <link
      linkend="storage-file-layout"><envar>PGDATA</envar></link>/<link
      linkend="guc-wal-summary-keep-time"><filename>pg_wal/summaries</filename></link>
      (Yushi Ogiwara)
      <ulink url="&commit_baseurl;4e1fad378">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Fujii Masao <fujii@postgresql.org>
2024-09-30 [559efce1d] Add num_done counter to the pg_stat_checkpointer view.
-->

      <listitem>
      <para>
      Add column <link
      linkend="monitoring-pg-stat-checkpointer-view"><structname>pg_stat_checkpointer</structname></link>.<structfield>num_done</structfield>
      to report the number of completed checkpoints (Anton A. Melnikov)
      <ulink url="&commit_baseurl;559efce1d">&sect;</ulink>
      </para>

      <para>
      Columns <structfield>num_timed</structfield> and
      <structfield>num_requested</structfield> count both completed and
      skipped checkpoints.
      </para>
      </listitem>

<!--
Author: Fujii Masao <fujii@postgresql.org>
2024-10-02 [17cc5f666] Fix inconsistent reporting of checkpointer stats.
-->

      <listitem>
      <para>
      Add column
      <structname>pg_stat_checkpointer</structname>.<structfield>slru_written</structfield>
      to report <acronym>SLRU</acronym> buffers written (Nitin Jadhav)
      <ulink url="&commit_baseurl;17cc5f666">&sect;</ulink>
      </para>

      <para>
      Also, modify the checkpoint server log message to report separate
      shared buffer and <acronym>SLRU</acronym> buffer values.
      </para>
      </listitem>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2024-11-11 [e7a9496de] Add two attributes to pg_stat_database for parallel work
-->

      <listitem>
      <para>
      Add columns to <link
      linkend="monitoring-pg-stat-database-view"><structname>pg_stat_database</structname></link>
      to report parallel worker activity (Benoit Lobréau)
      <ulink url="&commit_baseurl;e7a9496de">&sect;</ulink>
      </para>

      <para>
      The new columns are
      <structfield>parallel_workers_to_launch</structfield> and
      <structfield>parallel_workers_launched</structfield>.
      </para>
      </listitem>

<!--
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
2025-03-18 [62d712ecf] Introduce squashing of constant lists in query jumbling
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
2025-03-27 [9fbd53dea] Remove the query_id_squash_values GUC
Author: Álvaro Herrera <alvherre@kurilemu.de>
Branch: master Release: REL_18_BR [c2da1a5d6] 2025-06-24 19:36:32 +0200
-->

      <listitem>
      <para>
      Have <link linkend="guc-compute-query-id">query id</link> computation
      of constant lists consider only the first and last constants (Dmitry
      Dolgov, Sami Imseih)
      <ulink url="&commit_baseurl;62d712ecf">&sect;</ulink>
      <ulink url="&commit_baseurl;9fbd53dea">&sect;</ulink>
      <ulink url="&commit_baseurl;c2da1a5d6">&sect;</ulink>
      </para>

      <para>
      Jumbling is used by <xref linkend="pgstatstatements"/>.
      </para>
      </listitem>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2025-03-26 [787514b30] Use relation name instead of OID in query jumbling for R
-->

      <listitem>
      <para>
      Adjust query id computations to group together queries using the
      same relation name (Michael Paquier, Sami Imseih)
      <ulink url="&commit_baseurl;787514b30">&sect;</ulink>
      </para>

      <para>
      This is true even if the tables in different schemas have different
      column names.
      </para>
      </listitem>

<!--
Author: David Rowley <drowley@postgresql.org>
2024-07-01 [12227a1d5] Add context type field to pg_backend_memory_contexts
-->

      <listitem>
      <para>
      Add column <link
      linkend="view-pg-backend-memory-contexts"><structname>pg_backend_memory_contexts</structname></link>.<structfield>type</structfield>
      to report the type of memory context (David Rowley)
      <ulink url="&commit_baseurl;12227a1d5">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: David Rowley <drowley@postgresql.org>
2024-07-25 [32d3ed816] Add path column to pg_backend_memory_contexts view
-->

      <listitem>
      <para>
      Add column
      <structname>pg_backend_memory_contexts</structname>.<structfield>path</structfield>
      to show memory context parents (Melih Mutlu)
      <ulink url="&commit_baseurl;32d3ed816">&sect;</ulink>
      </para>
      </listitem>

     </itemizedlist>

    </sect4>

    <sect4 id="release-18-privileges">
     <title>Privileges</title>

     <itemizedlist>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2024-07-04 [4564f1ceb] Add pg_get_acl() to get the ACL for a database object
Author: Michael Paquier <michael@paquier.xyz>
2024-07-10 [d898665bf] Extend pg_get_acl() to handle sub-object IDs
-->

      <listitem>
      <para>
      Add function <link
      linkend="functions-info-object-table"><function>pg_get_acl()</function></link>
      to retrieve database access control details (Joel Jacobson)
      <ulink url="&commit_baseurl;4564f1ceb">&sect;</ulink>
      <ulink url="&commit_baseurl;d898665bf">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Fujii Masao <fujii@postgresql.org>
2024-09-12 [4eada203a] Add has_largeobject_privilege function.
-->

      <listitem>
      <para>
      Add function <link
      linkend="functions-info-access-table"><function>has_largeobject_privilege()</function></link>
      to check large object privileges (Yugo Nagata)
      <ulink url="&commit_baseurl;4eada203a">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Fujii Masao <fujii@postgresql.org>
2025-04-04 [0d6c47766] Extend ALTER DEFAULT PRIVILEGES to define default privil
-->

      <listitem>
      <para>
      Allow <xref linkend="sql-alterdefaultprivileges"/> to define
      large object default privileges (Takatsuka Haruka, Yugo Nagata,
      Laurenz Albe)
      <ulink url="&commit_baseurl;0d6c47766">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Nathan Bossart <nathan@postgresql.org>
2024-07-09 [ccd38024b] Introduce pg_signal_autovacuum_worker.
-->

      <listitem>
      <para>
      Add predefined role <link
      linkend="predefined-roles"><literal>pg_signal_autovacuum_worker</literal></link>
      (Kirill Reshke)
      <ulink url="&commit_baseurl;ccd38024b">&sect;</ulink>
      </para>

      <para>
      This allows sending signals to autovacuum workers.
      </para>
      </listitem>

     </itemizedlist>

    </sect4>

    <sect4 id="release-18-server-config">
     <title>Server Configuration</title>

     <itemizedlist>

<!--
Author: Daniel Gustafsson <dgustafsson@postgresql.org>
2025-02-20 [b3f0be788] Add support for OAUTHBEARER SASL mechanism
-->

      <listitem>
      <para>
      Add support for the <link linkend="auth-oauth">OAuth authentication
      method</link> (Jacob Champion, Daniel Gustafsson, Thomas Munro)
      <ulink url="&commit_baseurl;b3f0be788">&sect;</ulink>
      </para>

      <para>
      This adds an <literal>oauth</literal> authentication method to <link
      linkend="auth-pg-hba-conf"><filename>pg_hba.conf</filename></link>,
      libpq OAuth options, a server variable <xref
      linkend="guc-oauth-validator-libraries"/> to load
      token validation libraries, and a configure flag <link
      linkend="configure-option-with-libcurl"><option>--with-libcurl</option></link>
      to add the required compile-time libraries.
      </para>
      </listitem>

<!--
Author: Daniel Gustafsson <dgustafsson@postgresql.org>
2024-10-24 [45188c2ea] Support configuring TLSv1.3 cipher suites
-->

      <listitem>
      <para>
      Add server variable <xref linkend="guc-ssl-tls13-ciphers"/> to allow
      specification of multiple colon-separated TLSv1.3 cipher suites
      (Erica Zhang, Daniel Gustafsson)
      <ulink url="&commit_baseurl;45188c2ea">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Daniel Gustafsson <dgustafsson@postgresql.org>
2025-03-18 [daa02c6bd] Add X25519 to the default set of curves
-->

      <listitem>
      <para>
      Change server variable <xref linkend="guc-ssl-groups"/>'s default
      to include elliptic curve X25519 (Daniel Gustafsson, Jacob Champion)
      <ulink url="&commit_baseurl;daa02c6bd">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Daniel Gustafsson <dgustafsson@postgresql.org>
2024-10-24 [3d1ef3a15] Support configuring multiple ECDH curves
-->

      <listitem>
      <para>
      Rename server variable <varname>ssl_ecdh_curve</varname> to <xref
      linkend="guc-ssl-groups"/> and allow multiple colon-separated
      <acronym>ECDH</acronym> curves to be specified (Erica Zhang,
      Daniel Gustafsson)
      <ulink url="&commit_baseurl;3d1ef3a15">&sect;</ulink>
      </para>

      <para>
      The previous name still works.
      </para>
      </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
2025-04-02 [a460251f0] Make cancel request keys longer
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
2024-07-29 [9d9b9d46f] Move cancel key generation to after forking the backend
-->

      <listitem>
      <para>
      Make <link linkend="functions-admin-signal-table">cancel request
      keys</link> 256 bits (Heikki Linnakangas, Jelte Fennema-Nio)
      <ulink url="&commit_baseurl;a460251f0">&sect;</ulink>
      <ulink url="&commit_baseurl;9d9b9d46f">&sect;</ulink>
      </para>

      <para>
      This is only possible when the server and client support wire
      protocol version 3.2, introduced in this release.
      </para>
      </listitem>

<!--
Author: Nathan Bossart <nathan@postgresql.org>
2025-01-06 [c758119e5] Allow changing autovacuum_max_workers without restarting
-->

      <listitem>
      <para>
      Add server variable <xref linkend="guc-autovacuum-worker-slots"/>
      to specify the maximum number of background workers (Nathan Bossart)
      <ulink url="&commit_baseurl;c758119e5">&sect;</ulink>
      </para>

      <para>
      With this variable set, <xref linkend="guc-autovacuum-max-workers"/>
      can be adjusted at runtime up to this maximum without a server
      restart.
      </para>
      </listitem>

<!--
Author: Nathan Bossart <nathan@postgresql.org>
2025-02-05 [306dc520b] Introduce autovacuum_vacuum_max_threshold.
-->

      <listitem>
      <para>
      Allow specification of the fixed number of dead tuples that will
      trigger an <link linkend="autovacuum">autovacuum</link> (Nathan
      Bossart, Frédéric Yhuel)
      <ulink url="&commit_baseurl;306dc520b">&sect;</ulink>
      </para>

      <para>
      The server variable is <xref
      linkend="guc-autovacuum-vacuum-max-threshold"/>.  Percentages are
      still used for triggering.
      </para>
      </listitem>

<!--
Author: Andres Freund <andres@anarazel.de>
2025-03-24 [adb5f85fa] Redefine max_files_per_process to control additionally o
-->

      <listitem>
      <para>
      Change server variable <xref linkend="guc-max-files-per-process"/>
      to limit only files opened by a backend (Andres Freund)
      <ulink url="&commit_baseurl;adb5f85fa">&sect;</ulink>
      </para>

      <para>
      Previously files opened by the postmaster were also counted toward
      this limit.
      </para>
      </listitem>

<!--
Author: Nathan Bossart <nathan@postgresql.org>
2024-07-26 [0dcaea569] Introduce num_os_semaphores GUC.
-->

      <listitem>
      <para>
      Add server variable <xref linkend="guc-num-os-semaphores"/> to
      report the required number of semaphores (Nathan Bossart)
      <ulink url="&commit_baseurl;0dcaea569">&sect;</ulink>
      </para>

      <para>
      This is useful for operating system configuration.
      </para>
      </listitem>

<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2025-03-19 [4f7f7b037] extension_control_path
Author: Peter Eisentraut <peter@eisentraut.org>
2025-05-02 [81eaaa2c4] Make "directory" setting work with extension_control_pat
-->

      <listitem>
      <para>
      Add server variable <xref linkend="guc-extension-control-path"/> to
      specify the location of extension control files (Peter Eisentraut,
      Matheus Alcantara)
      <ulink url="&commit_baseurl;4f7f7b037">&sect;</ulink>
      <ulink url="&commit_baseurl;81eaaa2c4">&sect;</ulink>
      </para>
      </listitem>

     </itemizedlist>

    </sect4>

    <sect4 id="release-18-replication">
     <title>Streaming Replication and Recovery</title>

     <itemizedlist>

<!--
Author: Amit Kapila <akapila@postgresql.org>
2025-02-19 [ac0e33136] Invalidate inactive replication slots.
-->

      <listitem>
      <para>
      Allow inactive replication slots to be automatically invalidated using
      server variable <xref linkend="guc-idle-replication-slot-timeout"/>
      (Nisha Moond, Bharath Rupireddy)
      <ulink url="&commit_baseurl;ac0e33136">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Masahiko Sawada <msawada@postgresql.org>
2025-03-21 [04ff636cb] Add GUC option to control maximum active replication ori
-->

      <listitem>
      <para>
      Add server variable <xref
      linkend="guc-max-active-replication-origins"/> to control the
      maximum active replication origins (Euler Taveira)
      <ulink url="&commit_baseurl;04ff636cb">&sect;</ulink>
      </para>

      <para>
      This was previously controlled by <xref
      linkend="guc-max-replication-slots"/>, but this new setting allows
      a higher origin count in cases where fewer slots are required.
      </para>
      </listitem>

     </itemizedlist>

    </sect4>

    <sect4 id="release-18-logical">
     <title><link linkend="logical-replication">Logical Replication</link></title>

     <itemizedlist>

<!--
Author: Amit Kapila <akapila@postgresql.org>
2024-10-30 [745217a05] Replicate generated columns when specified in the column
Author: Amit Kapila <akapila@postgresql.org>
2024-11-07 [7054186c4] Replicate generated columns when 'publish_generated_colu
Author: Amit Kapila <akapila@postgresql.org>
2024-12-04 [87ce27de6] Ensure stored generated columns must be published when r
Author: Amit Kapila <akapila@postgresql.org>
2025-01-30 [6252b1eaf] Doc: Generated column replication.
-->

      <listitem>
      <para>
      Allow the values of <link
      linkend="sql-createtable-parms-generated-stored">generated
      columns</link> to be logically replicated (Shubham Khanna, Vignesh C,
      Zhijie Hou, Shlok Kyal, Peter Smith)
      <ulink url="&commit_baseurl;745217a05">&sect;</ulink>
      <ulink url="&commit_baseurl;7054186c4">&sect;</ulink>
      <ulink url="&commit_baseurl;87ce27de6">&sect;</ulink>
      <ulink url="&commit_baseurl;6252b1eaf">&sect;</ulink>
      </para>

      <para>
      If the publication specifies a column list, all specified
      columns, generated and non-generated, are published.
      Without a specified column list, publication option
      <literal>publish_generated_columns</literal> controls whether
      generated columns are published. Previously generated columns
      were not replicated and the subscriber had to compute
      the values if possible;  this is particularly useful for
      non-<productname>PostgreSQL</productname> subscribers which lack
      such a capability.
      </para>
      </listitem>

<!--
Author: Amit Kapila <akapila@postgresql.org>
2024-10-28 [1bf1140be] Change the default value of the streaming option to 'par
-->

      <listitem>
      <para>
      Change the default <xref linkend="sql-createsubscription"/> streaming
      option from <literal>off</literal> to <literal>parallel</literal>
      (Vignesh C)
      <ulink url="&commit_baseurl;1bf1140be">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Amit Kapila <akapila@postgresql.org>
2024-07-24 [1462aad2e] Allow altering of two_phase option of a SUBSCRIPTION.
Author: Amit Kapila <akapila@postgresql.org>
2025-04-03 [4868c96bc] Fix slot synchronization for two_phase enabled slots.
-->

      <listitem>
      <para>
      Allow <xref linkend="sql-altersubscription"/> to change the
      replication slot's two-phase commit behavior (Hayato Kuroda, Ajin
      Cherian, Amit Kapila, Zhijie Hou)
      <ulink url="&commit_baseurl;1462aad2e">&sect;</ulink>
      <ulink url="&commit_baseurl;4868c96bc">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Amit Kapila <akapila@postgresql.org>
2024-08-20 [9758174e2] Log the conflicts while applying changes in logical repl
Author: Amit Kapila <akapila@postgresql.org>
2024-08-22 [edcb71258] Doc: explain the log format of logical replication confl
Author: Amit Kapila <akapila@postgresql.org>
2024-08-29 [640178c92] Rename the conflict types for the origin differ cases.
Author: Amit Kapila <akapila@postgresql.org>
2024-09-04 [6c2b5edec] Collect statistics about conflicts in logical replicatio
Author: Amit Kapila <akapila@postgresql.org>
2025-03-24 [73eba5004] Detect and Log multiple_unique_conflicts type conflict.
-->

      <listitem>
      <para>
      Log <link linkend="hot-standby-conflict">conflicts</link> while
      applying logical replication changes (Zhijie Hou, Nisha Moond)
      <ulink url="&commit_baseurl;9758174e2">&sect;</ulink>
      <ulink url="&commit_baseurl;edcb71258">&sect;</ulink>
      <ulink url="&commit_baseurl;640178c92">&sect;</ulink>
      <ulink url="&commit_baseurl;6c2b5edec">&sect;</ulink>
      <ulink url="&commit_baseurl;73eba5004">&sect;</ulink>
      </para>

      <para>
      Also report in new columns of <link
      linkend="monitoring-pg-stat-subscription-stats"><structname>pg_stat_subscription_stats</structname></link>.
      </para>
      </listitem>

     </itemizedlist>

    </sect4>

   </sect3>

   <sect3 id="release-18-utility">
    <title>Utility Commands</title>

    <itemizedlist>

<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2025-02-07 [83ea6c540] Virtual generated columns
Author: Peter Eisentraut <peter@eisentraut.org>
2025-03-28 [cdc168ad4] Add support for not-null constraints on virtual generate
Author: Richard Guo <rguo@postgresql.org>
2025-02-25 [1e4351af3] Expand virtual generated columns in the planner
-->

     <listitem>
     <para>
     Allow <link linkend="sql-createtable-parms-generated-stored">generated
     columns</link> to be virtual, and make them the default (Peter
     Eisentraut, Jian He, Richard Guo, Dean Rasheed)
     <ulink url="&commit_baseurl;83ea6c540">&sect;</ulink>
     <ulink url="&commit_baseurl;cdc168ad4">&sect;</ulink>
     <ulink url="&commit_baseurl;1e4351af3">&sect;</ulink>
     </para>

     <para>
     Virtual generated columns generate their values when the columns
     are read, not written.  The write behavior can still be specified
     via the <literal>STORED</literal> option.
     </para>
     </listitem>

<!--
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
2025-01-16 [80feb727c] Add OLD/NEW support to RETURNING in DML queries.
-->

     <listitem>
     <para>
     Add <literal>OLD</literal>/<literal>NEW</literal> support to <link
     linkend="dml-returning"><literal>RETURNING</literal></link> in
     <acronym>DML</acronym> queries (Dean Rasheed)
     <ulink url="&commit_baseurl;80feb727c">&sect;</ulink>
     </para>

     <para>
     Previously <literal>RETURNING</literal> only returned new values for
     <xref linkend="sql-insert"/> and <xref linkend="sql-update"/>, and old
     values for <xref linkend="sql-delete"/>; <xref linkend="sql-merge"/>
     would return the appropriate value for the internal query executed.
     This new syntax allows the <literal>RETURNING</literal> list of
     <command>INSERT</command>/<command>UPDATE</command>/<command>DELETE</command>/<command>MERGE</command>
     to explicitly return old and new values by using the special aliases
     <literal>old</literal> and <literal>new</literal>.  These aliases
     can be renamed to avoid identifier conflicts.
     </para>
     </listitem>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2025-02-19 [302cf1575] Add support for LIKE in CREATE FOREIGN TABLE
-->

     <listitem>
     <para>
     Allow foreign tables to be created like existing local tables
     (Zhang Mingli)
     <ulink url="&commit_baseurl;302cf1575">&sect;</ulink>
     </para>

     <para>
     The syntax is <link linkend="sql-createforeigntable"><command>CREATE
     FOREIGN TABLE ... LIKE</command></link>.
     </para>
     </listitem>

<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2024-11-27 [85b7efa1c] Support LIKE with nondeterministic collations
-->

     <listitem>
     <para>
     Allow <link linkend="functions-like"><literal>LIKE</literal></link>
     with <link linkend="collation-nondeterministic">nondeterministic
     collations</link> (Peter Eisentraut)
     <ulink url="&commit_baseurl;85b7efa1c">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2025-02-21 [329304c90] Support text position search functions with nondetermini
-->

     <listitem>
     <para>
     Allow text position search functions with nondeterministic collations
     (Peter Eisentraut)
     <ulink url="&commit_baseurl;329304c90">&sect;</ulink>
     </para>

     <para>
     These used to generate an error.
     </para>
     </listitem>

<!--
Author: Jeff Davis <jdavis@postgresql.org>
2025-01-17 [d3d098316] Support PG_UNICODE_FAST locale in the builtin collation
-->

     <listitem>
     <para>
     Add builtin collation provider <link
     linkend="locale-providers"><literal>PG_UNICODE_FAST</literal></link>
     (Jeff Davis)
     <ulink url="&commit_baseurl;d3d098316">&sect;</ulink>
     </para>

     <para>
     This locale supports case mapping, but sorts in code point order,
     not natural language order.
     </para>
     </listitem>

<!--
Author: David Rowley <drowley@postgresql.org>
2024-09-24 [62ddf7ee9] Add ONLY support for VACUUM and ANALYZE
-->

     <listitem>
     <para>
     Allow <xref linkend="sql-vacuum"/> and <xref linkend="sql-analyze"/>
     to process partitioned tables without processing their children
     (Michael Harris)
     <ulink url="&commit_baseurl;62ddf7ee9">&sect;</ulink>
     </para>

     <para>
     This is enabled with the new <literal>ONLY</literal> option.  This is
     useful since autovacuum does not process partitioned tables, just
     its children.
     </para>
     </listitem>

<!--
Author: Jeff Davis <jdavis@postgresql.org>
2024-10-11 [e839c8ecc] Create functions pg_set_relation_stats, pg_clear_relatio
Author: Jeff Davis <jdavis@postgresql.org>
2024-10-24 [d32d14639] Add functions pg_restore_relation_stats(), pg_restore_at
Author: Jeff Davis <jdavis@postgresql.org>
2025-03-25 [650ab8aaf] Stats: use schemaname/relname instead of regclass.
-->

     <listitem>
     <para>
     Add functions to modify per-relation and per-column optimizer
     statistics (Corey Huinker)
     <ulink url="&commit_baseurl;e839c8ecc">&sect;</ulink>
     <ulink url="&commit_baseurl;d32d14639">&sect;</ulink>
     <ulink url="&commit_baseurl;650ab8aaf">&sect;</ulink>
     </para>

     <para>
     The functions are <link
     linkend="functions-admin-statsmod"><function>pg_restore_relation_stats()</function></link>,
     <function>pg_restore_attribute_stats()</function>,
     <function>pg_clear_relation_stats()</function>, and
     <function>pg_clear_attribute_stats()</function>.
     </para>
     </listitem>


<!--
Author: Thomas Munro <tmunro@postgresql.org>
2025-04-08 [f78ca6f3e] Introduce file_copy_method setting.
-->

     <listitem>
     <para>
     Add server variable <xref linkend="guc-file-copy-method"/> to control
     the file copying method (Nazir Bilal Yavuz)
     <ulink url="&commit_baseurl;f78ca6f3e">&sect;</ulink>
     </para>

     <para>
     This controls whether <link
     linkend="sql-createdatabase"><command>CREATE DATABASE
     ... STRATEGY=FILE_COPY</command></link> and <link
     linkend="sql-alterdatabase"><command>ALTER DATABASE ... SET
     TABLESPACE</command></link> uses file copy or clone.
     </para>
     </listitem>

    </itemizedlist>

    <sect4 id="release-18-constraints">
     <title><link linkend="ddl-constraints">Constraints</link></title>

     <itemizedlist>

<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2024-09-17 [fc0438b4e] Add temporal PRIMARY KEY and UNIQUE constraints
Author: Peter Eisentraut <peter@eisentraut.org>
2024-09-17 [89f908a6d] Add temporal FOREIGN KEY contraints
-->

      <listitem>
      <para>
      Allow the specification of non-overlapping <link
      linkend="sql-createtable-parms-primary-key"><literal>PRIMARY
      KEY</literal></link>, <link linkend="sql-createtable-parms-unique">
      <literal>UNIQUE</literal></link>, and
      <link linkend="sql-createtable-parms-references">foreign key</link>
      constraints (Paul A. Jungwirth)
      <ulink url="&commit_baseurl;fc0438b4e">&sect;</ulink>
      <ulink url="&commit_baseurl;89f908a6d">&sect;</ulink>
      </para>

      <para>
      This is specified by <literal>WITHOUT OVERLAPS</literal> for
      <literal>PRIMARY KEY</literal> and <literal>UNIQUE</literal>, and by
      <literal>PERIOD</literal> for foreign keys, all applied to the last
      specified column.
      </para>
      </listitem>

<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2025-01-11 [ca87c415e] Add support for NOT ENFORCED in CHECK constraints
Author: Peter Eisentraut <peter@eisentraut.org>
2025-04-02 [eec0040c4] Add support for NOT ENFORCED in foreign key constraints
-->

      <listitem>
      <para>
      Allow <link
      linkend="sql-createtable-parms-check"><literal>CHECK</literal></link>
      and <link linkend="sql-createtable-parms-references">foreign
      key</link> constraints to be specified as <literal>NOT
      ENFORCED</literal> (Amul Sul)
      <ulink url="&commit_baseurl;ca87c415e">&sect;</ulink>
      <ulink url="&commit_baseurl;eec0040c4">&sect;</ulink>
      </para>

      <para>
      This also adds column <link
      linkend="catalog-pg-constraint"><structname>pg_constraint</structname></link>.<structfield>conenforced</structfield>.
      </para>
      </listitem>

<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2024-11-15 [9321d2fdf] Fix collation handling for foreign keys
-->

      <listitem>
      <para>
      Require <link
      linkend="sql-createtable-parms-references">primary/foreign key</link>
      relationships to use either deterministic collations or the the
      same nondeterministic collations (Peter Eisentraut)
      <ulink url="&commit_baseurl;9321d2fdf">&sect;</ulink>
      </para>

      <para>
      The restore of a <xref linkend="app-pgdump"/>, also used by <xref
      linkend="pgupgrade"/>, will fail if these requirements are not met;
      schema changes must be made for these upgrade methods to succeed.
      </para>
      </listitem>

<!--
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
2024-11-08 [14e87ffa5] Add pg_constraint rows for not-null constraints
Author: Fujii Masao <fujii@postgresql.org>
Branch: master Release: REL_18_BR [81ce602d4] 2025-06-26 20:25:34 +0900
-->

      <listitem>
      <para>
      Store column <link
      linkend="sql-createtable-parms-not-null"><literal>NOT
      NULL</literal></link> specifications in <link
      linkend="catalog-pg-constraint"><structname>pg_constraint</structname></link>
      (Álvaro Herrera, Bernd Helmle)
      <ulink url="&commit_baseurl;14e87ffa5">&sect;</ulink>
      <ulink url="&commit_baseurl;81ce602d4">&sect;</ulink>
      </para>

      <para>
      This allows names to be specified for <literal>NOT NULL</literal>
      constraint.  This also adds <literal>NOT NULL</literal> constraints
      to foreign tables and <literal>NOT NULL</literal> inheritance
      control to local tables.
      </para>
      </listitem>

<!--
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
2025-04-07 [a379061a2] Allow NOT NULL constraints to be added as NOT VALID
-->

      <listitem>
      <para>
      Allow <xref linkend="sql-altertable"/> to set the <literal>NOT
      VALID</literal> attribute of <literal>NOT NULL</literal> constraints
      (Rushabh Lathia, Jian He)
      <ulink url="&commit_baseurl;a379061a2">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
2025-03-05 [f4e53e10b] Add ALTER TABLE ... ALTER CONSTRAINT ... SET [NO] INHERI
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
2025-03-27 [4a02af8b1] Simplify syntax for ALTER TABLE ALTER CONSTRAINT NO INHE
-->

      <listitem>
      <para>
      Allow modification of the inheritability of <literal>NOT
      NULL</literal> constraints (Suraj Kharage, Álvaro Herrera)
      <ulink url="&commit_baseurl;f4e53e10b">&sect;</ulink>
      <ulink url="&commit_baseurl;4a02af8b1">&sect;</ulink>
      </para>

      <para>
      The syntax is <link linkend="sql-altertable"><command>ALTER TABLE
      ... ALTER CONSTRAINT ... [NO] INHERIT</command></link>.
      </para>
      </listitem>

<!--
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
2025-01-23 [b663b9436] Allow NOT VALID foreign key constraints on partitioned t
-->

      <listitem>
      <para>
      Allow <literal>NOT VALID</literal> foreign key constraints on
      partitioned tables (Amul Sul)
      <ulink url="&commit_baseurl;b663b9436">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
2024-09-30 [4dea33ce7] Don't disallow DROP of constraints ONLY on partitioned t
-->

      <listitem>
      <para>
      Allow <link
      linkend="sql-altertable-desc-drop-constraint">dropping</link>
      of constraints <literal>ONLY</literal> on partitioned tables
      (Álvaro Herrera)
      <ulink url="&commit_baseurl;4dea33ce7">&sect;</ulink>
      </para>

      <para>
      This was previously erroneously prohibited.
      </para>
      </listitem>

     </itemizedlist>
    </sect4>

    <sect4 id="release-18-copy">
     <title><xref linkend="sql-copy"/></title>

     <itemizedlist>

<!--
Author: Fujii Masao <fujii@postgresql.org>
2024-10-08 [4ac2a9bec] Add REJECT_LIMIT option to the COPY command.
-->

      <listitem>
      <para>
      Add <literal>REJECT_LIMIT</literal> to control the number of invalid
      rows <command>COPY FROM</command> can ignore (Atsushi Torikoshi)
      <ulink url="&commit_baseurl;4ac2a9bec">&sect;</ulink>
      </para>

      <para>
      This is available when <literal>ON_ERROR = 'ignore'</literal>.
      </para>
      </listitem>

<!--
Author: Fujii Masao <fujii@postgresql.org>
2025-04-04 [534874fac] Allow "COPY table TO" command to copy rows from material
-->

      <listitem>
      <para>
      Allow <command>COPY TO</command> to copy rows from populated
      materialized views (Jian He)
      <ulink url="&commit_baseurl;534874fac">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Fujii Masao <fujii@postgresql.org>
2024-10-03 [e7834a1a2] Add LOG_VERBOSITY = 'silent' support to COPY command.
-->

      <listitem>
      <para>
      Add <command>COPY</command> <literal>LOG_VERBOSITY</literal> level
      <literal>silent</literal> to suppress log output of ignored rows
      (Atsushi Torikoshi)
      <ulink url="&commit_baseurl;e7834a1a2">&sect;</ulink>
      </para>

      <para>
      This new level suppresses output for discarded input rows when
      <literal>on_error = 'ignore'</literal>.
      </para>
      </listitem>

<!--
Author: Nathan Bossart <nathan@postgresql.org>
2025-02-06 [401a6956f] Disallow COPY FREEZE on foreign tables.
-->

      <listitem>
      <para>
      Disallow <command>COPY FREEZE</command> on foreign tables (Nathan
      Bossart)
      <ulink url="&commit_baseurl;401a6956f">&sect;</ulink>
      </para>

      <para>
      Previously, the <command>COPY</command> worked but the
      <literal>FREEZE</literal> was ignored, so disallow this command.
      </para>
      </listitem>

     </itemizedlist>
    </sect4>

    <sect4 id="release-18-explain">
     <title><xref linkend="sql-explain"/></title>

     <itemizedlist>

<!--
Author: David Rowley <drowley@postgresql.org>
2024-12-11 [c2a4078eb] Enable BUFFERS with EXPLAIN ANALYZE by default
-->

      <listitem>
      <para>
      Automatically include <literal>BUFFERS</literal> output in
      <command>EXPLAIN ANALYZE</command> (Guillaume Lelarge, David Rowley)
      <ulink url="&commit_baseurl;c2a4078eb">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2025-02-17 [320545bfc] Add information about WAL buffers being full to EXPLAIN
-->

      <listitem>
      <para>
      Add full <acronym>WAL</acronym> buffer count to <command>EXPLAIN
      (WAL)</command> output (Bertrand Drouvot)
      <ulink url="&commit_baseurl;320545bfc">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Peter Geoghegan <pg@bowt.ie>
2025-03-11 [0fbceae84] Show index search count in EXPLAIN ANALYZE, take 2.
-->

      <listitem>
      <para>
      In <command>EXPLAIN ANALYZE</command>, report the number of index
      lookups used per index scan node (Peter Geoghegan)
      <ulink url="&commit_baseurl;0fbceae84">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Robert Haas <rhaas@postgresql.org>
2025-02-21 [ddb17e387] Allow EXPLAIN to indicate fractional rows.
Author: Robert Haas <rhaas@postgresql.org>
2025-02-27 [95dbd827f] EXPLAIN: Always use two fractional digits for row counts
-->

      <listitem>
      <para>
      Modify <command>EXPLAIN</command> to output fractional row counts
      (Ibrar Ahmed, Ilia Evdokimov, Robert Haas)
      <ulink url="&commit_baseurl;ddb17e387">&sect;</ulink>
      <ulink url="&commit_baseurl;95dbd827f">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: David Rowley <drowley@postgresql.org>
2024-07-05 [1eff8279d] Add memory/disk usage for Material nodes in EXPLAIN
Author: David Rowley <drowley@postgresql.org>
2024-07-05 [53abb1e0e] Fix newly introduced issue in EXPLAIN for Materialize no
Author: Tatsuo Ishii <ishii@postgresql.org>
2024-09-17 [95d6e9af0] Add memory/disk usage for Window aggregate nodes in EXPL
Author: Tatsuo Ishii <ishii@postgresql.org>
2024-09-23 [40708acd6] Add memory/disk usage for more executor nodes.
-->

      <listitem>
      <para>
      Add memory and disk usage details to <literal>Material</literal>,
      <literal>Window Aggregate</literal>, and common table expression
      nodes to <command>EXPLAIN</command> output (David Rowley, Tatsuo
      Ishii)
      <ulink url="&commit_baseurl;1eff8279d">&sect;</ulink>
      <ulink url="&commit_baseurl;53abb1e0e">&sect;</ulink>
      <ulink url="&commit_baseurl;95d6e9af0">&sect;</ulink>
      <ulink url="&commit_baseurl;40708acd6">&sect;</ulink>
      </para>
      </listitem>


<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2025-03-11 [8b1b34254] Improve EXPLAIN's display of window functions.
-->

      <listitem>
      <para>
      Add details about window function arguments to
      <command>EXPLAIN</command> output (Tom Lane)
      <ulink url="&commit_baseurl;8b1b34254">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: David Rowley <drowley@postgresql.org>
2024-07-09 [5a1e6df3b] Show Parallel Bitmap Heap Scan worker stats in EXPLAIN A
-->

      <listitem>
      <para>
      Add <literal>Parallel Bitmap Heap Scan</literal> worker cache
      statistics to <command>EXPLAIN ANALYZE</command> (David Geier,
      Heikki Linnakangas, Donghang Lin, Alena Rybakina, David Rowley)
      <ulink url="&commit_baseurl;5a1e6df3b">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Robert Haas <rhaas@postgresql.org>
2024-08-21 [c01743aa4] Show number of disabled nodes in EXPLAIN ANALYZE output.
Author: David Rowley <drowley@postgresql.org>
2024-10-11 [161320b4b] Adjust EXPLAIN's output for disabled nodes
Author: David Rowley <drowley@postgresql.org>
2024-10-29 [84b8fccbe] Doc: add detail about EXPLAIN's "Disabled" property
-->

      <listitem>
      <para>
      Indicate disabled nodes in <command>EXPLAIN ANALYZE</command> output
      (Robert Haas, David Rowley, Laurenz Albe)
      <ulink url="&commit_baseurl;c01743aa4">&sect;</ulink>
      <ulink url="&commit_baseurl;161320b4b">&sect;</ulink>
      <ulink url="&commit_baseurl;84b8fccbe">&sect;</ulink>
      </para>
      </listitem>

     </itemizedlist>

    </sect4>

   </sect3>

   <sect3 id="release-18-datatypes">
    <title>Data Types</title>

    <itemizedlist>

<!--
Author: Jeff Davis <jdavis@postgresql.org>
2025-01-23 [4e7f62bc3] Add support for Unicode case folding.
Author: Jeff Davis <jdavis@postgresql.org>
2025-01-17 [286a365b9] Support Unicode full case mapping and conversion.
-->

     <listitem>
     <para>
     Improve <link linkend="collation-managing-standard">Unicode</link>
     full case mapping and conversion (Jeff Davis)
     <ulink url="&commit_baseurl;4e7f62bc3">&sect;</ulink>
     <ulink url="&commit_baseurl;286a365b9">&sect;</ulink>
     </para>

     <para>
     This adds the ability to do conditional and title case mapping,
     and case map single characters to multiple characters.
     </para>
     </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2025-01-24 [a5579a90a] Make jsonb casts to scalar types translate JSON null to
-->

     <listitem>
     <para>
     Allow <link linkend="datatype-json"><type>jsonb</type></link>
     <literal>null</literal> values to be cast to scalar types as
     <literal>NULL</literal> (Tom Lane)
     <ulink url="&commit_baseurl;a5579a90a">&sect;</ulink>
     </para>

     <para>
     Previously such casts generated an error.
     </para>
     </listitem>

<!--
Author: Andrew Dunstan <andrew@dunslane.net>
2025-03-05 [4603903d2] Allow json{b}_strip_nulls() to remove null array elements
-->

     <listitem>
     <para>
     Add optional parameter to <link
     linkend="functions-json-processing-table"><function>json{b}_strip_nulls</function></link>
     to allow removal of null array elements (Florents Tselai)
     <ulink url="&commit_baseurl;4603903d2">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2025-04-01 [6c12ae09f] Introduce a SQL-callable function array_sort(anyarray).
-->

     <listitem>
     <para>
     Add function <link
     linkend="array-functions-table"><function>array_sort()</function></link>
     which sorts an array's first dimension (Junwang Zhao, Jian He)
     <ulink url="&commit_baseurl;6c12ae09f">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2024-11-01 [49d6c7d8d] Add SQL function array_reverse()
-->

     <listitem>
     <para>
     Add function <link
     linkend="array-functions-table"><function>array_reverse()</function></link>
     which reverses an array's first dimension (Aleksander Alekseev)
     <ulink url="&commit_baseurl;49d6c7d8d">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Nathan Bossart <nathan@postgresql.org>
2025-03-13 [0697b2390] Add reverse(bytea).
-->

     <listitem>
     <para>
     Add function <link
     linkend="functions-string-other"><function>reverse()</function></link>
     to reverse bytea bytes (Aleksander Alekseev)
     <ulink url="&commit_baseurl;0697b2390">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
2025-03-07 [6da469bad] Allow casting between bytea and integer types.
-->

     <listitem>
     <para>
     Allow casting between integer types and <link
     linkend="datatype-binary"><type>bytea</type></link> (Aleksander
     Alekseev)
     <ulink url="&commit_baseurl;6da469bad">&sect;</ulink>
     </para>

     <para>
     The integer values are stored as <type>bytea</type> two's complement
     values.
     </para>
     </listitem>

<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2025-04-03 [82a46cca9] Update Unicode data to Unicode 16.0.0
-->

     <listitem>
     <para>
     Update Unicode data to <link
     linkend="collation-managing-standard">Unicode</link> 16.0.0 (Peter
     Eisentraut)
     <ulink url="&commit_baseurl;82a46cca9">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2025-02-18 [b464e51ab] Update to latest Snowball sources.
-->

     <listitem>
     <para>
     Add full text search <link
     linkend="textsearch-snowball-dictionary">stemming</link> for Estonian
     (Tom Lane)
     <ulink url="&commit_baseurl;b464e51ab">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2024-09-24 [cd838e200] Neaten up our choices of SQLSTATEs for XML-related error
-->

     <listitem>
     <para>
     Improve the <link linkend="datatype-xml"><type>XML</type></link>
     error codes to more closely match the <acronym>SQL</acronym> standard
     (Tom Lane)
     <ulink url="&commit_baseurl;cd838e200">&sect;</ulink>
     </para>

     <para>
     These errors are reported via <link
     linkend="errcodes-appendix"><literal>SQLSTATE</literal></link>.
     </para>
     </listitem>

    </itemizedlist>

   </sect3>

   <sect3 id="release-18-functions">
    <title>Functions</title>

    <itemizedlist>

<!--
Author: Jeff Davis <jdavis@postgresql.org>
2025-01-24 [bfc599206] Add SQL function CASEFOLD().
-->

     <listitem>
     <para>
     Add function <link
     linkend="functions-string-other"><function>casefold()</function></link>
     to allow for more sophisticated case-insensitive matching (Jeff Davis)
     <ulink url="&commit_baseurl;bfc599206">&sect;</ulink>
     </para>

     <para>
     This allows more accurate comparisons, i.e., a character can have
     multiple upper or lower case equivalents, or upper or lower case
     conversion changes the number of characters.
     </para>
     </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2024-07-11 [a0f1fce80] Add min and max aggregates for composite types (records)
Author: Tom Lane <tgl@sss.pgh.pa.us>
2024-10-08 [2d24fd942] Add min and max aggregates for bytea type.
-->

     <listitem>
     <para>
     Allow <link
     linkend="functions-aggregate-table"><function>MIN()</function></link>/<link
     linkend="functions-aggregate-table"><function>MAX()</function></link>
     aggregates on arrays and composite types (Aleksander Alekseev,
     Marat Buharov)
     <ulink url="&commit_baseurl;a0f1fce80">&sect;</ulink>
     <ulink url="&commit_baseurl;2d24fd942">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2024-08-16 [6be39d77a] Fix extraction of week and quarter fields from intervals
-->

     <listitem>
     <para>
     Add a <literal>WEEK</literal> option to <link
     linkend="functions-datetime-extract"><function>EXTRACT()</function></link>
     (Tom Lane)
     <ulink url="&commit_baseurl;6be39d77a">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2024-08-16 [6be39d77a] Fix extraction of week and quarter fields from intervals
-->

     <listitem>
     <para>
     Improve the output <literal>EXTRACT(QUARTER ...)</literal> for
     negative values (Tom Lane)
     <ulink url="&commit_baseurl;6be39d77a">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2025-01-22 [172e6b3ad] Support RN (roman-numeral format) in to_number().
-->

     <listitem>
     <para>
     Add roman numeral support to <link
     linkend="functions-formatting-table"><function>to_number()</function></link>
     (Hunaid Sohail)
     <ulink url="&commit_baseurl;172e6b3ad">&sect;</ulink>
     </para>

     <para>
     This is accessed via the <literal>RN</literal> pattern.
     </para>
     </listitem>

<!--
Author: Masahiko Sawada <msawada@postgresql.org>
2024-12-11 [78c5e141e] Add UUID version 7 generation function.
-->

     <listitem>
     <para>
     Add <link linkend="datatype-uuid"><type>UUID</type></link>
     version 7 generation function <link
     linkend="func_uuid_gen_table"><function>uuidv7()</function></link>
     (Andrey Borodin)
     <ulink url="&commit_baseurl;78c5e141e">&sect;</ulink>
     </para>

     <para>
     This <type>UUID</type> value is
     temporally sortable.  Function alias <link
     linkend="func_uuid_gen_table"><function>uuidv4()</function></link>
     has been added to explicitly generate version 4 UUIDs.
     </para>
     </listitem>

<!--
Author: Nathan Bossart <nathan@postgresql.org>
2024-08-12 [760162fed] Add user-callable CRC functions.
-->

     <listitem>
     <para>
     Add functions <link
     linkend="functions-binarystring-other"><function>crc32()</function></link>
     and <link
     linkend="functions-binarystring-other"><function>crc32c()</function></link>
     to compute <acronym>CRC</acronym> values (Aleksander Alekseev)
     <ulink url="&commit_baseurl;760162fed">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
2025-03-26 [a3b6dfd41] Add support for gamma() and lgamma() functions.
-->

     <listitem>
     <para>
     Add math functions <link
     linkend="functions-math-func-table"><function>gamma()</function></link>
     and <link
     linkend="functions-math-func-table"><function>lgamma()</function></link>
     (Dean Rasheed)
     <ulink url="&commit_baseurl;a3b6dfd41">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2025-03-03 [246dedc5d] Allow =&gt; syntax for named cursor arguments in plpgsql.
-->

     <listitem>
     <para>
     Allow <literal>=&gt;</literal> syntax for named cursor arguments in
     <link linkend="plpgsql">PL/pgSQL</link> (Pavel Stehule)
     <ulink url="&commit_baseurl;246dedc5d">&sect;</ulink>
     </para>

     <para>
     We previously only accepted <literal>:=</literal>.
     </para>
     </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2024-07-25 [580f8727c] Add argument names to the regexp_XXX functions.
-->

     <listitem>
     <para>
     Allow <link
     linkend="functions-posix-regexp"><function>regexp_match[es]()</function></link>/<link
     linkend="functions-posix-regexp"><function>regexp_like()</function></link>/<link
     linkend="functions-posix-regexp"><function>regexp_replace()</function></link>/<link
     linkend="functions-posix-regexp"><function>regexp_count()</function></link>/<link
     linkend="functions-posix-regexp"><function>regexp_instr()</function></link>/<link
     linkend="functions-posix-regexp"><function>regexp_substr()</function></link>/<link
     linkend="functions-posix-regexp"><function>regexp_split_to_table()</function></link>/<link
     linkend="functions-posix-regexp"><function>regexp_split_to_array()</function></link>
     to use named arguments (Jian He)
     <ulink url="&commit_baseurl;580f8727c">&sect;</ulink>
     </para>
     </listitem>

    </itemizedlist>

   </sect3>

   <sect3 id="release-18-libpq">
    <title><xref linkend="libpq"/></title>

    <itemizedlist>

<!--
Author: Robert Haas <rhaas@postgresql.org>
2024-09-09 [cdb6b0fdb] Add PQfullProtocolVersion() to surface the precise proto
-->

     <listitem>
     <para>
     Add function <link
     linkend="libpq-PQfullProtocolVersion"><function>PQfullProtocolVersion()</function></link>
     to report the full, including minor, protocol version number (Jacob
     Champion, Jelte Fennema-Nio)
     <ulink url="&commit_baseurl;cdb6b0fdb">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
2025-04-02 [285613c60] libpq: Add min/max_protocol_version connection options
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
2025-04-02 [507034910] libpq: Handle NegotiateProtocolVersion message different
-->

     <listitem>
     <para>
     Add libpq connection <link
     linkend="libpq-connect-ssl-max-protocol-version">parameters</link>
     and <link linkend="libpq-envars">environment variables</link> to
     specify the minimum and maximum acceptable protocol version for
     connections (Jelte Fennema-Nio)
     <ulink url="&commit_baseurl;285613c60">&sect;</ulink>
     <ulink url="&commit_baseurl;507034910">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Tomas Vondra <tomas.vondra@postgresql.org>
2024-08-19 [28a1121fd] Mark search_path as GUC_REPORT
Author: Tomas Vondra <tomas.vondra@postgresql.org>
2024-08-19 [0d06a7eac] Document that search_path is reported by the server
-->

     <listitem>
     <para>
     Report <xref linkend="guc-search-path"/> changes to the client
     (Alexander Kukushkin, Jelte Fennema-Nio, Tomas Vondra)
     <ulink url="&commit_baseurl;28a1121fd">&sect;</ulink>
     <ulink url="&commit_baseurl;0d06a7eac">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
2024-08-12 [ea92f3a0a] libpq: Trace frontend authentication challenges
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
2024-08-14 [a5c6b8f22] libpq: Trace responses to SSLRequest and GSSENCRequest
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
2024-08-16 [b8b3f861f] libpq: Trace all messages received from the server
Author: Robert Haas <rhaas@postgresql.org>
2025-02-24 [e87c14b19] libpq: Trace all NegotiateProtocolVersion fields
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
2024-08-09 [7adec2d5f] libpq: Trace StartupMessage/SSLRequest/GSSENCRequest cor
-->

     <listitem>
     <para>
     Add <link
     linkend="libpq-PQtrace"><function>PQtrace()</function></link> output
     for all message types, including authentication (Jelte Fennema-Nio)
     <ulink url="&commit_baseurl;ea92f3a0a">&sect;</ulink>
     <ulink url="&commit_baseurl;a5c6b8f22">&sect;</ulink>
     <ulink url="&commit_baseurl;b8b3f861f">&sect;</ulink>
     <ulink url="&commit_baseurl;e87c14b19">&sect;</ulink>
     <ulink url="&commit_baseurl;7adec2d5f">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Daniel Gustafsson <dgustafsson@postgresql.org>
2025-04-03 [2da74d8d6] libpq: Add support for dumping SSL key material to file
-->

     <listitem>
     <para>
     Add libpq connection parameter <link
     linkend="libpq-connect-sslkeylogfile"><varname>sslkeylogfile</varname></link>
     which dumps out <acronym>SSL</acronym> key material (Abhishek Chanda,
     Daniel Gustafsson)
     <ulink url="&commit_baseurl;2da74d8d6">&sect;</ulink>
     </para>

     <para>
     This is useful for debugging.
     </para>
     </listitem>

<!--
Author: Thomas Munro <tmunro@postgresql.org>
2025-03-25 [3c86223c9] libpq: Deprecate pg_int64.
-->

     <listitem>
     <para>
     Modify some libpq function signatures to use
     <literal>int64_t</literal> (Thomas Munro)
     <ulink url="&commit_baseurl;3c86223c9">&sect;</ulink>
     </para>

     <para>
     These previously used <literal>pg_int64</literal>, which is now
     deprecated.
     </para>
     </listitem>

    </itemizedlist>

   </sect3>

   <sect3 id="release-18-psql">
    <title><xref linkend="app-psql"/></title>

    <itemizedlist>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2024-08-22 [d55322b0d] psql: Add more meta-commands able to use the extended pr
Author: Michael Paquier <michael@paquier.xyz>
Branch: master Release: REL_18_BR [fc39b286a] 2025-06-24 13:12:46 +0900
-->

     <listitem>
     <para>
     Allow <application>psql</application> to parse, bind, and close
     named prepared statements (Anthonin Bonnefoy, Michael Paquier)
     <ulink url="&commit_baseurl;d55322b0d">&sect;</ulink>
     <ulink url="&commit_baseurl;fc39b286a">&sect;</ulink>
     </para>

     <para>
     This is accomplished with new commands <link
     linkend="app-psql-meta-command-parse"><literal>\parse</literal></link>,
     <link
     linkend="app-psql-meta-command-bind-named"><literal>\bind_named</literal></link>,
     and <link
     linkend="app-psql-meta-command-close-prepared"><literal>\close_prepared</literal></link>.
     </para>
     </listitem>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2025-02-21 [41625ab8e] psql: Add support for pipelines
Author: Michael Paquier <michael@paquier.xyz>
2025-03-18 [17caf6644] psql: Add \sendpipeline to send query buffers while in a
Author: Michael Paquier <michael@paquier.xyz>
2025-03-19 [2cce0fe44] psql: Allow queries terminated by semicolons while in pi
-->

     <listitem>
     <para>
     Add <application>psql</application> backslash commands to allowing
     issuance of pipeline queries (Anthonin Bonnefoy)
     <ulink url="&commit_baseurl;41625ab8e">&sect;</ulink>
     <ulink url="&commit_baseurl;17caf6644">&sect;</ulink>
     <ulink url="&commit_baseurl;2cce0fe44">&sect;</ulink>
     </para>

     <para>
     The new commands are <link
     linkend="app-psql-meta-command-pipeline"><literal>\startpipeline</literal></link>,
     <literal>\syncpipeline</literal>, <literal>\sendpipeline</literal>,
     <literal>\endpipeline</literal>, <literal>\flushrequest</literal>,
     <literal>\flush</literal>, and <literal>\getresults</literal>.
     </para>
     </listitem>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2025-02-25 [3ce357584] psql: Add pipeline status to prompt and some state varia
-->

     <listitem>
     <para>
     Allow adding pipeline status to the <application>psql</application>
     prompt and add related state variables (Anthonin Bonnefoy)
     <ulink url="&commit_baseurl;3ce357584">&sect;</ulink>
     </para>

     <para>
     The new prompt character is <literal>%P</literal> and
     the new <application>psql</application> variables are <link
     linkend="app-psql-variables-pipeline-sync-count"><literal>PIPELINE_SYNC_COUNT</literal></link>,
     <link
     linkend="app-psql-variables-pipeline-command-count"><literal>PIPELINE_COMMAND_COUNT</literal></link>,
     and <link
     linkend="app-psql-variables-pipeline-result-count"><literal>PIPELINE_RESULT_COUNT</literal></link>.
     </para>
     </listitem>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2024-12-18 [477728b5d] psql: Add more information about service name
-->

     <listitem>
     <para>
     Allow adding the connection service name to the
     <application>psql</application> prompt or access it via
     <application>psql</application> variable (Michael Banck)
     <ulink url="&commit_baseurl;477728b5d">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
2025-01-14 [00f4c2959] psql: Add option to use expanded mode to all list comman
-->

     <listitem>
     <para>
     Add <application>psql</application> option to use expanded mode on
     all list commands (Dean Rasheed)
     <ulink url="&commit_baseurl;00f4c2959">&sect;</ulink>
     </para>

     <para>
     Adding backslash suffix <literal>x</literal> enables this.
     </para>
     </listitem>

<!--
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
2025-02-22 [bba2fbc62] Change \conninfo to use tabular format
-->

     <listitem>
     <para>
     Change <application>psql</application>'s <xref
     linkend="app-psql-meta-command-conninfo"/> to use tabular format
     and include more information (Álvaro Herrera, Maiquel Grassi,
     Hunaid Sohail)
     <ulink url="&commit_baseurl;bba2fbc62">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
2025-01-14 [2355e5111] psql: Add leakproof indicator to \df+, \do+, \dAo+, and
-->

     <listitem>
     <para>
     Add function's leakproof indicator
     to <application>psql</application>'s <link
     linkend="app-psql-meta-command-df-lc"><literal>\df+</literal></link>,
     <literal>\do+</literal>, <literal>\dAo+</literal>, and
     <literal>\dC+</literal> outputs (Yugo Nagata)
     <ulink url="&commit_baseurl;2355e5111">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2024-07-02 [978f38c77] Add information about access method for partitioned rela
-->

     <listitem>
     <para>
     Add access method details for partitioned relations in <link
     linkend="app-psql-meta-command-dp-uc"><literal>\dP+</literal></link>
     (Justin Pryzby)
     <ulink url="&commit_baseurl;978f38c77">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Magnus Hagander <magnus@hagander.net>
2025-03-24 [d696406a9] psql: show default extension version in \dx output
-->

     <listitem>
     <para>
     Add <literal>default_version</literal>
     to the <application>psql</application> <link
     linkend="app-psql-meta-command-dx-lc"><literal>\dx</literal></link>
     extension output (Magnus Hagander)
     <ulink url="&commit_baseurl;d696406a9">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Daniel Gustafsson <dgustafsson@postgresql.org>
2025-03-25 [1a759c832] psql: Make default \watch interval configurable
-->

     <listitem>
     <para>
     Add <application>psql</application> variable <xref
     linkend="app-psql-variables-watch-interval"/> to set the default <link
     linkend="app-psql-meta-command-watch"><literal>\watch</literal></link>
     wait time (Daniel Gustafsson)
     <ulink url="&commit_baseurl;1a759c832">&sect;</ulink>
     </para>
     </listitem>

    </itemizedlist>

   </sect3>

   <sect3 id="release-18-server-apps">
    <title>Server Applications</title>

    <itemizedlist>

<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2024-10-01 [983a588e0] initdb: Add new option "- -no-data-checksums"
Author: Peter Eisentraut <peter@eisentraut.org>
2024-10-16 [04bec894a] initdb: Change default to using data checksums.
-->

     <listitem>
     <para>
     Change <xref linkend="app-initdb"/> to default to enabling checksums
     (Greg Sabino Mullane)
     <ulink url="&commit_baseurl;983a588e0">&sect;</ulink>
     <ulink url="&commit_baseurl;04bec894a">&sect;</ulink>
     </para>

     <para>
     The new <application>initdb</application> option
     <option>--no-data-checksums</option> disables checksums.
     </para>
     </listitem>

<!--
Author: Nathan Bossart <nathan@postgresql.org>
2025-03-25 [cf131fa94] initdb: Add - -no-sync-data-files.
-->

     <listitem>
     <para>
     Add <application>initdb</application> option
     <option>--no-sync-data-files</option> to avoid syncing heap/index
     files (Nathan Bossart)
     <ulink url="&commit_baseurl;cf131fa94">&sect;</ulink>
     </para>

     <para>
     <application>initdb</application> option <option>--no-sync</option>
     is still available to avoid syncing any files.
     </para>
     </listitem>

<!--
Author: Nathan Bossart <nathan@postgresql.org>
2025-03-18 [edba754f0] vacuumdb: Add option for analyzing only relations missin
Author: Nathan Bossart <nathan@postgresql.org>
2025-04-30 [987910502] vacuumdb: Don't skip empty relations in - -missing-stats-
-->

     <listitem>
     <para>
     Add <xref linkend="app-vacuumdb"/> option
     <option>--missing-stats-only</option> to compute only missing
     optimizer statistics (Corey Huinker, Nathan Bossart)
     <ulink url="&commit_baseurl;edba754f0">&sect;</ulink>
     <ulink url="&commit_baseurl;987910502">&sect;</ulink>
     </para>

     <para>
     This option can only be run by superusers and can only
     be used with options <option>--analyze-only</option> and
     <option>--analyze-in-stages</option>.
     </para>
     </listitem>

<!--
Author: Robert Haas <rhaas@postgresql.org>
2025-03-17 [99aeb8470] pg_combinebackup: Add -k, - -link option.
-->

     <listitem>
     <para>
     Add <xref linkend="app-pgcombinebackup"/> option
     <option>-k</option>/<option>--link</option> to enable hard linking
     (Israel Barth Rubio, Robert Haas)
     <ulink url="&commit_baseurl;99aeb8470">&sect;</ulink>
     </para>

     <para>
     Only some files can be hard linked.  This should not be used if the
     backups will be used independently.
     </para>
     </listitem>

<!--
Author: Robert Haas <rhaas@postgresql.org>
2024-09-27 [8dfd31290] pg_verifybackup: Verify tar-format backups.
-->

     <listitem>
     <para>
     Allow <xref linkend="app-pgverifybackup"/> to verify tar-format
     backups (Amul Sul)
     <ulink url="&commit_baseurl;8dfd31290">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Masahiko Sawada <msawada@postgresql.org>
2025-03-12 [4ecdd4110] pg_rewind: Add dbname to primary_conninfo when using - -w
-->

     <listitem>
     <para>
     If <xref linkend="app-pgrewind"/>'s <option>--source-server</option>
     specifies a database name, use it in
     <option>--write-recovery-conf</option> output (Masahiko Sawada)
     <ulink url="&commit_baseurl;4ecdd4110">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Masahiko Sawada <msawada@postgresql.org>
2025-02-21 [30666d185] pg_resetwal: Add - -char-signedness option to change the
-->

     <listitem>
     <para>
     Add <xref linkend="app-pgresetwal"/> option
     <option>--char-signedness</option> to change the default
     <type>char</type> signedness (Masahiko Sawada)
     <ulink url="&commit_baseurl;30666d185">&sect;</ulink>
     </para>
     </listitem>

    </itemizedlist>


    <sect4 id="release-18-pgdump">
     <title><link
     linkend="app-pgdump"><application>pg_dump</application></link>/<link
     linkend="app-pg-dumpall"><application>pg_dumpall</application></link>/<link
     linkend="app-pgrestore"><application>pg_restore</application></link></title>

     <itemizedlist>

<!--
Author: Jeff Davis <jdavis@postgresql.org>
2025-03-25 [bde2fb797] Add pg_dump - -with-{schema|data|statistics} options.
Author: Jeff Davis <jdavis@postgresql.org>
2025-08-02 [a3e8dc143] Simplify options in pg_dump and pg_restore.
-->

      <listitem>
      <para>
      Add <xref linkend="app-pgdump"/> option <option>--statistics</option>
      (Jeff Davis)
      <ulink url="&commit_baseurl;bde2fb797">&sect;</ulink>
      <ulink url="&commit_baseurl;a3e8dc143">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Nathan Bossart <nathan@postgresql.org>
2025-03-25 [9c49f0e8c] pg_dump: Add - -sequence-data.
Author: Nathan Bossart <nathan@postgresql.org>
2025-05-07 [acea3fc49] pg_dumpall: Add - -sequence-data.
-->

      <listitem>
      <para>
      Add <application>pg_dump</application> and <xref
      linkend="app-pg-dumpall"/> option <option>--sequence-data</option> to
      dump sequence data that would normally be excluded (Nathan Bossart)
      <ulink url="&commit_baseurl;9c49f0e8c">&sect;</ulink>
      <ulink url="&commit_baseurl;acea3fc49">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Jeff Davis <jdavis@postgresql.org>
2025-02-20 [1fd1bd871] Transfer statistics during pg_upgrade.
-->

      <listitem>
      <para>
      Add <xref linkend="app-pgdump"/>, <xref linkend="app-pg-dumpall"/>,
      and <xref linkend="app-pgrestore"/> options
      <option>--statistics-only</option>, <option>--no-statistics</option>,
      <option>--no-data</option>, and <option>--no-schema</option>
      (Corey Huinker, Jeff Davis)
      <ulink url="&commit_baseurl;1fd1bd871">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2025-03-16 [cd3c45125] pg_dump, pg_dumpall, pg_restore: Add - -no-policies optio
-->

      <listitem>
      <para>
      Add option <option>--no-policies</option> to disable row level
      security policy processing in <xref linkend="app-pgdump"/>,
      <xref linkend="app-pg-dumpall"/>, <xref linkend="app-pgrestore"/>
      (Nikolay Samokhvalov)
      <ulink url="&commit_baseurl;cd3c45125">&sect;</ulink>
      </para>

      <para>
      This is useful for migrating to systems with different policies.
      </para>
      </listitem>

     </itemizedlist>

    </sect4>

    <sect4 id="release-18-pgupgrade">
     <title><xref linkend="pgupgrade"/></title>

     <itemizedlist>

<!--
Author: Jeff Davis <jdavis@postgresql.org>
2025-02-20 [1fd1bd871] Transfer statistics during pg_upgrade.
Author: Nathan Bossart <nathan@postgresql.org>
2025-03-18 [c9d502eb6] Update guidance for running vacuumdb after pg_upgrade.
Author: Nathan Bossart <nathan@postgresql.org>
2025-04-30 [d5f1b6a75] Further adjust guidance for running vacuumdb after pg_up
Author: Jeff Davis <jdavis@postgresql.org>
2025-02-20 [1fd1bd871] Transfer statistics during pg_upgrade.
-->

      <listitem>
      <para>
      Allow <application>pg_upgrade</application> to preserve optimizer
      statistics (Corey Huinker, Jeff Davis, Nathan Bossart)
      <ulink url="&commit_baseurl;1fd1bd871">&sect;</ulink>
      <ulink url="&commit_baseurl;c9d502eb6">&sect;</ulink>
      <ulink url="&commit_baseurl;d5f1b6a75">&sect;</ulink>
      <ulink url="&commit_baseurl;1fd1bd871">&sect;</ulink>
      </para>

      <para>
      Extended statistics are not preserved.  Also add
      <application>pg_upgrade</application> option
      <option>--no-statistics</option> to disable statistics preservation.
      </para>
      </listitem>

<!--
Author: Nathan Bossart <nathan@postgresql.org>
2024-09-16 [40e2e5e92] Introduce framework for parallelizing various pg_upgrade
Author: Nathan Bossart <nathan@postgresql.org>
2024-09-16 [6d3d2e8e5] pg_upgrade: Parallelize retrieving relation information.
Author: Nathan Bossart <nathan@postgresql.org>
2024-09-16 [7baa36de5] pg_upgrade: Parallelize subscription check.
Author: Nathan Bossart <nathan@postgresql.org>
2024-09-16 [46cad8b31] pg_upgrade: Parallelize retrieving loadable libraries.
Author: Nathan Bossart <nathan@postgresql.org>
2024-09-16 [6ab8f27bc] pg_upgrade: Parallelize retrieving extension updates.
Author: Nathan Bossart <nathan@postgresql.org>
2024-09-16 [bbf83cab9] pg_upgrade: Parallelize data type checks.
Author: Nathan Bossart <nathan@postgresql.org>
2024-09-16 [9db3018cf] pg_upgrade: Parallelize contrib/isn check.
Author: Nathan Bossart <nathan@postgresql.org>
2024-09-16 [c34eabfbb] pg_upgrade: Parallelize postfix operator check.
Author: Nathan Bossart <nathan@postgresql.org>
2024-09-16 [cf2f82a37] pg_upgrade: Parallelize incompatible polymorphics check.
Author: Nathan Bossart <nathan@postgresql.org>
2024-09-16 [f93f5f7b9] pg_upgrade: Parallelize WITH OIDS check.
Author: Nathan Bossart <nathan@postgresql.org>
2024-09-16 [c880cf258] pg_upgrade: Parallelize encoding conversion check.
-->

      <listitem>
      <para>
      Allow <application>pg_upgrade</application> to process database
      checks in parallel (Nathan Bossart)
      <ulink url="&commit_baseurl;40e2e5e92">&sect;</ulink>
      <ulink url="&commit_baseurl;6d3d2e8e5">&sect;</ulink>
      <ulink url="&commit_baseurl;7baa36de5">&sect;</ulink>
      <ulink url="&commit_baseurl;46cad8b31">&sect;</ulink>
      <ulink url="&commit_baseurl;6ab8f27bc">&sect;</ulink>
      <ulink url="&commit_baseurl;bbf83cab9">&sect;</ulink>
      <ulink url="&commit_baseurl;9db3018cf">&sect;</ulink>
      <ulink url="&commit_baseurl;c34eabfbb">&sect;</ulink>
      <ulink url="&commit_baseurl;cf2f82a37">&sect;</ulink>
      <ulink url="&commit_baseurl;f93f5f7b9">&sect;</ulink>
      <ulink url="&commit_baseurl;c880cf258">&sect;</ulink>
      </para>

      <para>
      This is controlled by the existing <option>--jobs</option> option.
      </para>
      </listitem>

<!--
Author: Nathan Bossart <nathan@postgresql.org>
2025-03-25 [626d7236b] pg_upgrade: Add - -swap for faster file transfer.
-->

      <listitem>
      <para>
      Add <application>pg_upgrade</application> option
      <option>--swap</option> to swap directories rather than copy, clone,
      or link files (Nathan Bossart)
      <ulink url="&commit_baseurl;626d7236b">&sect;</ulink>
      </para>

      <para>
      This mode is potentially the fastest.
      </para>
      </listitem>

<!--
Author: Masahiko Sawada <msawada@postgresql.org>
2025-02-21 [a8238f87f] pg_upgrade: Preserve default char signedness value from
Author: Masahiko Sawada <msawada@postgresql.org>
2025-02-21 [1aab68059] pg_upgrade: Add - -set-char-signedness to set the default
-->

      <listitem>
      <para>
      Add <application>pg_upgrade</application> option
      <option>--set-char-signedness</option> to set the default
      <type>char</type> signedness of new cluster (Masahiko Sawada)
      <ulink url="&commit_baseurl;a8238f87f">&sect;</ulink>
      <ulink url="&commit_baseurl;1aab68059">&sect;</ulink>
      </para>

      <para>
      This is to handle cases where a
      pre-<productname>PostgreSQL</productname> 18 cluster's default
      <acronym>CPU</acronym> signedness does not match the new cluster.
      </para>
      </listitem>

     </itemizedlist>

    </sect4>

    <sect4 id="release-18-logicalrep-app">
     <title>Logical Replication Applications</title>

     <itemizedlist>

<!--
Author: Amit Kapila <akapila@postgresql.org>
2025-03-28 [fb2ea12f4] pg_createsubscriber: Add '- -all' option.
-->

      <listitem>
      <para>
      Add <xref linkend="app-pgcreatesubscriber"/> option
      <option>--all</option> to create logical replicas for all databases
      (Shubham Khanna)
      <ulink url="&commit_baseurl;fb2ea12f4">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Amit Kapila <akapila@postgresql.org>
2025-03-20 [e5aeed4b8] pg_createsubscriber: Add -R publications option.
Author: Peter Eisentraut <peter@eisentraut.org>
Branch: master Release: REL_18_BR [60dda7bbc] 2025-06-25 10:50:43 +0200
-->

      <listitem>
      <para>
      Add <application>pg_createsubscriber</application> option
      <option>--clean</option> to remove publications (Shubham Khanna)
      <ulink url="&commit_baseurl;e5aeed4b8">&sect;</ulink>
      <ulink url="&commit_baseurl;60dda7bbc">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Amit Kapila <akapila@postgresql.org>
2025-02-26 [e117cfb2f] Add two-phase option in pg_createsubscriber.
-->

      <listitem>
      <para>
      Add <application>pg_createsubscriber</application> option
      <option>--enable-two-phase</option> to enable prepared transactions
      (Shubham Khanna)
      <ulink url="&commit_baseurl;e117cfb2f">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Masahiko Sawada <msawada@postgresql.org>
2025-04-04 [cf2655a90] pg_recvlogical: Add - -failover option.
-->

      <listitem>
      <para>
      Add <xref linkend="app-pgrecvlogical"/> option
      <option>--enable-failover</option> to specify failover slots (Hayato Kuroda)
      <ulink url="&commit_baseurl;cf2655a90">&sect;</ulink>
      </para>

      <para>
      Also add option <option>--enable-two-phase</option> as a synonym
      for <option>--two-phase</option>, and deprecate the latter.
      </para>
      </listitem>

<!--
Author: Fujii Masao <fujii@postgresql.org>
2025-03-25 [c68100aa4] Allow pg_recvlogical - -drop-slot to work without - -dbnam
-->

      <listitem>
      <para>
      Allow <application>pg_recvlogical</application>
      <option>--drop-slot</option> to work without
      <option>--dbname</option> (Hayato Kuroda)
      <ulink url="&commit_baseurl;c68100aa4">&sect;</ulink>
      </para>
      </listitem>

     </itemizedlist>

    </sect4>

   </sect3>

   <sect3 id="release-18-source-code">
    <title>Source Code</title>

    <itemizedlist>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2024-07-05 [4b211003e] Support loading of injection points
Author: Michael Paquier <michael@paquier.xyz>
2024-07-18 [a0a5869a8] Add INJECTION_POINT_CACHED() to run injection points dir
-->

     <listitem>
     <para>
     Separate the loading and running of <link
     linkend="xfunc-addin-injection-points">injection points</link>
     (Michael Paquier, Heikki Linnakangas)
     <ulink url="&commit_baseurl;4b211003e">&sect;</ulink>
     <ulink url="&commit_baseurl;a0a5869a8">&sect;</ulink>
     </para>

     <para>
     Injection points can now be created, but not run, via <link
     linkend="xfunc-addin-injection-points"><function>INJECTION_POINT_LOAD()</function></link>,
     and such injection points can be run via <link
     linkend="xfunc-addin-injection-points"><function>INJECTION_POINT_CACHED()</function></link>.
     </para>
     </listitem>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2025-05-10 [371f2db8b] Add support for runtime arguments in injection points
-->

     <listitem>
     <para>
     Support runtime arguments in injection points (Michael Paquier)
     <ulink url="&commit_baseurl;371f2db8b">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
2024-07-26 [20e0e7da9] Add test for early backend startup errors
-->

     <listitem>
     <para>
     Allow inline injection point test code with <link
     linkend="xfunc-addin-injection-points"><function>IS_INJECTION_POINT_ATTACHED()</function></link>
     (Heikki Linnakangas)
     <ulink url="&commit_baseurl;20e0e7da9">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: David Rowley <drowley@postgresql.org>
2024-08-05 [ca6fde922] Optimize JSON escaping using SIMD
-->

     <listitem>
     <para>
     Improve the performance of processing long <link
     linkend="datatype-json"><type>JSON</type></link> strings using
     <acronym>SIMD</acronym> (Single Instruction Multiple Data) (David
     Rowley)
     <ulink url="&commit_baseurl;ca6fde922">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: John Naylor <john.naylor@postgresql.org>
2025-04-06 [3c6e8c123] Compute CRC32C using AVX-512 instructions where availabl
-->

     <listitem>
     <para>
     Speed up CRC32C calculations using x86 <acronym>AVX</acronym>-512
     instructions (Raghuveer Devulapalli, Paul Amonson)
     <ulink url="&commit_baseurl;3c6e8c123">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Nathan Bossart <nathan@postgresql.org>
2025-03-28 [6be53c276] Optimize popcount functions with ARM Neon intrinsics.
Author: Nathan Bossart <nathan@postgresql.org>
2025-03-28 [519338ace] Optimize popcount functions with ARM SVE intrinsics.
-->

     <listitem>
     <para>
     Add <acronym>ARM</acronym> Neon and <acronym>SVE CPU</acronym>
     intrinsics for popcount (integer bit counting) (Chiranmoy
     Bhattacharya, Devanga Susmitha, Rama Malladi)
     <ulink url="&commit_baseurl;6be53c276">&sect;</ulink>
     <ulink url="&commit_baseurl;519338ace">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
2024-07-09 [ca481d3c9] Optimise numeric multiplication for short inputs.
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
2024-08-15 [c4e44224c] Extend mul_var_short() to 5 and 6-digit inputs.
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
2024-08-15 [8dc28d7eb] Optimise numeric multiplication using base-NBASE^2 arith
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
2024-10-04 [9428c001f] Speed up numeric division by always using the "fast" alg
-->

     <listitem>
     <para>
     Improve the speed of numeric multiplication and division (Joel
     Jacobson, Dean Rasheed)
     <ulink url="&commit_baseurl;ca481d3c9">&sect;</ulink>
     <ulink url="&commit_baseurl;c4e44224c">&sect;</ulink>
     <ulink url="&commit_baseurl;8dc28d7eb">&sect;</ulink>
     <ulink url="&commit_baseurl;9428c001f">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Tomas Vondra <tomas.vondra@postgresql.org>
2025-04-07 [65c298f61] Add support for basic NUMA awareness
Author: Tomas Vondra <tomas.vondra@postgresql.org>
2025-04-07 [8cc139bec] Introduce pg_shmem_allocations_numa view
Author: Tomas Vondra <tomas.vondra@postgresql.org>
2025-04-07 [ba2a3c230] Add pg_buffercache_numa view with NUMA node info
-->

     <listitem>
     <para>
     Add configure option <link
     linkend="configure-option-with-libnuma"><option>--with-libnuma</option></link>
     to enable <acronym>NUMA</acronym> awareness (Jakub Wartak, Bertrand
     Drouvot)
     <ulink url="&commit_baseurl;65c298f61">&sect;</ulink>
     <ulink url="&commit_baseurl;8cc139bec">&sect;</ulink>
     <ulink url="&commit_baseurl;ba2a3c230">&sect;</ulink>
     </para>

     <para>
     The function <link
     linkend="functions-info-session-table"><function>pg_numa_available()</function></link>
     reports on <acronym>NUMA</acronym> awareness, and system views <link
     linkend="view-pg-shmem-allocations-numa"><structname>pg_shmem_allocations_numa</structname></link>
     and <link
     linkend="pgbuffercache-pg-buffercache-numa"><structname>pg_buffercache_numa</structname></link>
     which report on shared memory distribution across
     <acronym>NUMA</acronym> nodes.
     </para>
     </listitem>

<!--
Author: Nathan Bossart <nathan@postgresql.org>
2024-09-18 [b52c4fc3c] Add TOAST table to pg_index.
-->

     <listitem>
     <para>
     Add <link
     linkend="storage-toast"><acronym>TOAST</acronym></link> table to <link
     linkend="catalog-pg-index"><structname>pg_index</structname></link>
     to allow for very large expression indexes (Nathan Bossart)
     <ulink url="&commit_baseurl;b52c4fc3c">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: David Rowley <drowley@postgresql.org>
2024-12-20 [02a8d0c45] Remove pg_attribute.attcacheoff column
-->

     <listitem>
     <para>
     Remove column <link
     linkend="catalog-pg-attribute"><structname>pg_attribute</structname></link>.<structfield>attcacheoff</structfield>
     (David Rowley)
     <ulink url="&commit_baseurl;02a8d0c45">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Melanie Plageman <melanieplageman@gmail.com>
2025-03-03 [99f8f3fbb] Add relallfrozen to pg_class
-->

     <listitem>
     <para>
     Add column <link
     linkend="catalog-pg-class"><structname>pg_class</structname></link>.<structfield>relallfrozen</structfield>
     (Melanie Plageman)
     <ulink url="&commit_baseurl;99f8f3fbb">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2024-09-10 [56fead44d] Add amgettreeheight index AM API routine
Author: Peter Eisentraut <peter@eisentraut.org>
2025-03-07 [af4002b38] Rename amcancrosscompare
-->

     <listitem>
     <para>
     Add <link
     linkend="indexam"><structfield>amgettreeheight</structfield></link>,
     <literal>amconsistentequality</literal>, and
     <literal>amconsistentordering</literal> to the index access method
     <acronym>API</acronym> (Mark Dilger)
     <ulink url="&commit_baseurl;56fead44d">&sect;</ulink>
     <ulink url="&commit_baseurl;af4002b38">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2024-09-17 [7406ab623] Add stratnum GiST support function
-->

     <listitem>
     <para>
     Add GiST support function <link
     linkend="gist-extensibility"><function>stratnum()</function></link>
     (Paul A. Jungwirth)
     <ulink url="&commit_baseurl;7406ab623">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Masahiko Sawada <msawada@postgresql.org>
2025-02-21 [44fe30fda] Add default_char_signedness field to ControlFileData.
-->

     <listitem>
     <para>
     Record the default <acronym>CPU</acronym> signedness of
     <literal>char</literal> in <xref linkend="app-pgcontroldata"/>
     (Masahiko Sawada)
     <ulink url="&commit_baseurl;44fe30fda">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2025-03-12 [72a3d0462] Prepare for Python "Limited API" in PL/Python
Author: Peter Eisentraut <peter@eisentraut.org>
2025-03-14 [0793ab810] Activate Python "Limited API" in PL/Python
-->

     <listitem>
     <para>
     Add support for Python "Limited <acronym>API</acronym>" in <xref
     linkend="plpython"/> (Peter Eisentraut)
     <ulink url="&commit_baseurl;72a3d0462">&sect;</ulink>
     <ulink url="&commit_baseurl;0793ab810">&sect;</ulink>
     </para>

     <para>
     This helps prevent problems caused by
     <application>Python</application> 3.x version mismatches.
     </para>
     </listitem>

<!--
Author: Jacob Champion <jchampion@postgresql.org>
2025-04-29 [45363fca6] Bump the minimum supported Python version to 3.6.8
-->

     <listitem>
     <para>
     Change the minimum supported <application>Python</application>
     version to 3.6.8 (Jacob Champion)
     <ulink url="&commit_baseurl;45363fca6">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Daniel Gustafsson <dgustafsson@postgresql.org>
2024-09-02 [a70e01d43] Remove support for OpenSSL older than 1.1.0
Author: Daniel Gustafsson <dgustafsson@postgresql.org>
2024-10-24 [6c66b7443] Raise the minimum supported OpenSSL version to 1.1.1
-->

     <listitem>
     <para>
     Remove support for <application>OpenSSL</application> versions older
     than 1.1.1 (Daniel Gustafsson)
     <ulink url="&commit_baseurl;a70e01d43">&sect;</ulink>
     <ulink url="&commit_baseurl;6c66b7443">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2024-10-01 [972c2cd28] jit: Require at least LLVM 14, if enabled.
-->

     <listitem>
     <para>
     If <application>LLVM</application> is enabled, require version 14
     or later (Thomas Munro)
     <ulink url="&commit_baseurl;972c2cd28">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2025-03-26 [9324c8c58] Introduce PG_MODULE_MAGIC_EXT macro.
-->

     <listitem>
     <para>
     Add macro <link
     linkend="functions-info"><literal>PG_MODULE_MAGIC_EXT</literal></link>
     to allow extensions to report their name and version (Andrei Lepikhov)
     <ulink url="&commit_baseurl;9324c8c58">&sect;</ulink>
     </para>

     <para>
     This information can be access via the new function <link
     linkend="functions-info-session-table"><function>pg_get_loaded_modules()</function></link>.
     </para>
     </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2024-09-09 [218527d01] Don't bother checking the result of SPI_connect[_ext] an
-->

     <listitem>
     <para>
     Document that <link
     linkend="spi-spi-connect"><function>SPI_connect()</function></link>/<link
     linkend="spi-spi-connect"><function>SPI_connect_ext()</function></link>
     always returns success (<literal>SPI_OK_CONNECT</literal>) (Stepan
     Neretin)
     <ulink url="&commit_baseurl;218527d01">&sect;</ulink>
     </para>

     <para>
     Errors are always reported via <function>ereport()</function>.
     </para>
     </listitem>

<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2024-07-31 [e54a42ac9] Add API and ABI stability guidance to the C language doc
-->

     <listitem>
     <para>
     Add <link linkend="xfunc-api-abi-stability-guidance">documentation
     section</link> about <acronym>API</acronym> and <acronym>ABI</acronym>
     compatibility (David Wheeler, Peter Eisentraut)
     <ulink url="&commit_baseurl;e54a42ac9">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2025-01-27 [5afaba629] doc: Meson is not experimental on Windows
-->

     <listitem>
     <para>
     Remove the experimental designation of
     <application>Meson</application> builds on <systemitem
     class="osname">Windows</systemitem> (Aleksander Alekseev)
     <ulink url="&commit_baseurl;5afaba629">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Thomas Munro <tmunro@postgresql.org>
2024-07-30 [e25626677] Remove - -disable-spinlocks.
Author: Thomas Munro <tmunro@postgresql.org>
2024-07-30 [813852613] Remove - -disable-atomics, require 32 bit atomics.
-->

     <listitem>
     <para>
     Remove configure options <option>--disable-spinlocks</option> and
     <option>--disable-atomics</option> (Thomas Munro)
     <ulink url="&commit_baseurl;e25626677">&sect;</ulink>
     <ulink url="&commit_baseurl;813852613">&sect;</ulink>
     </para>

     <para>
     Thirty-two-bit atomic operations are now required.
     </para>
     </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2024-07-01 [edadeb071] Remove support for HPPA (a/k/a PA-RISC) architecture.
-->

     <listitem>
     <para>
     Remove support for the
     <acronym>HPPA</acronym>/<acronym>PA-RISC</acronym> architecture
     (Tom Lane)
     <ulink url="&commit_baseurl;edadeb071">&sect;</ulink>
     </para>
     </listitem>

    </itemizedlist>

   </sect3>

   <sect3 id="release-18-modules">
    <title>Additional Modules</title>

    <itemizedlist>

<!--
Author: Masahiko Sawada <msawada@postgresql.org>
2024-10-14 [7cdfeee32] Add contrib/pg_logicalinspect.
-->

     <listitem>
     <para>
     Add extension <xref linkend="pglogicalinspect"/> to inspect logical
     snapshots (Bertrand Drouvot)
     <ulink url="&commit_baseurl;7cdfeee32">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Robert Haas <rhaas@postgresql.org>
2025-03-26 [8d5ceb113] pg_overexplain: Additional EXPLAIN options for debugging
-->

     <listitem>
     <para>
     Add extension <xref linkend="pgoverexplain"/> which adds debug details
     to <link linkend="sql-explain"><command>EXPLAIN</command></link>
     output (Robert Haas)
     <ulink url="&commit_baseurl;8d5ceb113">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Fujii Masao <fujii@postgresql.org>
2024-07-26 [c297a47c5] postgres_fdw: Add "used_in_xact" column to postgres_fdw_
Author: Fujii Masao <fujii@postgresql.org>
2024-07-26 [857df3cef] postgres_fdw: Add connection status check to postgres_fd
Author: Fujii Masao <fujii@postgresql.org>
2024-09-18 [4f08ab554] postgres_fdw: Extend postgres_fdw_get_connections to ret
Author: Fujii Masao <fujii@postgresql.org>
2025-03-03 [fe186bda7] postgres_fdw: Extend postgres_fdw_get_connections to ret
-->

     <listitem>
     <para>
     Add output columns to <link
     linkend="postgres-fdw-functions"><function>postgres_fdw_get_connections()</function></link>
     (Hayato Kuroda, Sagar Dilip Shedge)
     <ulink url="&commit_baseurl;c297a47c5">&sect;</ulink>
     <ulink url="&commit_baseurl;857df3cef">&sect;</ulink>
     <ulink url="&commit_baseurl;4f08ab554">&sect;</ulink>
     <ulink url="&commit_baseurl;fe186bda7">&sect;</ulink>
     </para>

     <para>
     New output column <structfield>used_in_xact</structfield> indicates
     if the foreign data wrapper is being used by a current transaction,
     <structfield>closed</structfield> indicates if it is closed,
     <structfield>user_name</structfield> indicates the user name, and
     <structfield>remote_backend_pid</structfield> indicates the remote
     backend process identifier.
     </para>
     </listitem>

<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2025-01-15 [761c79508] postgres_fdw: SCRAM authentication pass-through
-->

     <listitem>
     <para>
     Allow <link linkend="auth-password"><acronym>SCRAM</acronym></link>
     authentication from the client to be passed to <xref
     linkend="postgres-fdw"/> servers (Matheus Alcantara, Peter Eisentraut)
     <ulink url="&commit_baseurl;761c79508">&sect;</ulink>
     </para>

     <para>
     This avoids storing <application>postgres_fdw</application>
     authentication information in the database, and is
     enabled with the <application>postgres_fdw</application> <link
     linkend="postgres-fdw-option-use-scram-passthrough"><literal>use_scram_passthrough</literal></link>
     connection option.  libpq uses new connection parameters
     <xref linkend="libpq-connect-scram-client-key"/> and <xref
     linkend="libpq-connect-scram-server-key"/>.
     </para>
     </listitem>

<!--
Author: Peter Eisentraut <peter@eisentraut.org>
2025-03-26 [3642df265] dblink: SCRAM authentication pass-through
-->

     <listitem>
     <para>
     Allow <acronym>SCRAM</acronym> authentication from the client to be
     passed to <xref linkend="dblink"/> servers (Matheus Alcantara)
     <ulink url="&commit_baseurl;3642df265">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Fujii Masao <fujii@postgresql.org>
2024-10-03 [a1c4c8a9e] file_fdw: Add on_error and log_verbosity options to file
-->

     <listitem>
     <para>
     Add <literal>on_error</literal> and <literal>log_verbosity</literal>
     options to <xref linkend="file-fdw"/> (Atsushi Torikoshi)
     <ulink url="&commit_baseurl;a1c4c8a9e">&sect;</ulink>
     </para>

     <para>
     These control how <application>file_fdw</application> handles and
     reports invalid file rows.
     </para>
     </listitem>

<!--
Author: Fujii Masao <fujii@postgresql.org>
2024-11-20 [6c8f67032] file_fdw: Add REJECT_LIMIT option to file_fdw.
-->

     <listitem>
     <para>
     Add <literal>reject_limit</literal> to control the number of
     invalid rows <application>file_fdw</application> can ignore (Atsushi
     Torikoshi)
     <ulink url="&commit_baseurl;6c8f67032">&sect;</ulink>
     </para>

     <para>
     This is active when <literal>ON_ERROR = 'ignore'</literal>.
     </para>
     </listitem>

<!--
Author: Nathan Bossart <nathan@postgresql.org>
2025-01-07 [f7e1b3828] Add passwordcheck.min_password_length.
-->

     <listitem>
     <para>
     Add configurable variable <varname>min_password_length</varname> to
     <xref linkend="passwordcheck"/> (Emanuele Musella, Maurizio Boriani)
     <ulink url="&commit_baseurl;f7e1b3828">&sect;</ulink>
     </para>

     <para>
     This controls the minimum password length.
     </para>
     </listitem>

<!--
Author: Tatsuo Ishii <ishii@postgresql.org>
2024-10-11 [cae0f3c40] pgbench: Improve result outputs related to failed transa
-->

     <listitem>
     <para>
     Have <xref linkend="pgbench"/> report the number of failed, retried,
     or skipped transactions in per-script reports (Yugo Nagata)
     <ulink url="&commit_baseurl;cae0f3c40">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
2025-03-16 [448904423] contrib/isn: Make weak mode a GUC setting, and fix relat
-->

     <listitem>
     <para>
     Add <xref linkend="isn"/> server variable <literal>weak</literal>
     to control invalid check digit acceptance (Viktor Holmberg)
     <ulink url="&commit_baseurl;448904423">&sect;</ulink>
     </para>

     <para>
     This was previously only controlled by function <link
     linkend="isn-functions"><function>isn_weak()</function></link>.
     </para>
     </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
2025-04-03 [e4309f73f] Add support for sorted gist index builds to btree_gist
-->

     <listitem>
     <para>
     Allow values to be sorted to speed <xref linkend="btree-gist"/>
     index builds (Bernd Helmle, Andrey Borodin)
     <ulink url="&commit_baseurl;e4309f73f">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Tomas Vondra <tomas.vondra@postgresql.org>
2025-03-29 [14ffaece0] amcheck: Add gin_index_check() to verify GIN index
-->

     <listitem>
     <para>
     Add <xref linkend="amcheck"/> check function <link
     linkend="amcheck-functions"><function>gin_index_check()</function></link>
     to verify <literal>GIN</literal> indexes (Grigory Kryachko, Heikki
     Linnakangas, Andrey Borodin)
     <ulink url="&commit_baseurl;14ffaece0">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Andres Freund <andres@anarazel.de>
2025-04-08 [dcf7e1697] Add pg_buffercache_evict_{relation,all} functions
-->

     <listitem>
     <para>
     Add functions <link
     linkend="pgbuffercache-pg-buffercache-evict-relation"><function>pg_buffercache_evict_relation()</function></link>
     and <link
     linkend="pgbuffercache-pg-buffercache-evict-all"><function>pg_buffercache_evict_all()</function></link>
     to evict unpinned shared buffers (Nazir Bilal Yavuz)
     <ulink url="&commit_baseurl;dcf7e1697">&sect;</ulink>
     </para>

     <para>
     The existing function <link
     linkend="pgbuffercache-pg-buffercache-evict"><function>pg_buffercache_evict()</function></link>
     now returns the buffer flush status.
     </para>
     </listitem>

<!--
Author: Robert Haas <rhaas@postgresql.org>
2025-03-18 [c65bc2e1d] Make it possible for loadable modules to add EXPLAIN opt
Author: Robert Haas <rhaas@postgresql.org>
2025-03-18 [4fd02bf7c] Add some new hooks so extensions can add details to EXPL
Author: Robert Haas <rhaas@postgresql.org>
2025-03-20 [50ba65e73] Add an additional hook for EXPLAIN option validation.
-->

     <listitem>
     <para>
     Allow extensions to install custom <xref linkend="sql-explain"/>
     options (Robert Haas, Sami Imseih)
     <ulink url="&commit_baseurl;c65bc2e1d">&sect;</ulink>
     <ulink url="&commit_baseurl;4fd02bf7c">&sect;</ulink>
     <ulink url="&commit_baseurl;50ba65e73">&sect;</ulink>
     </para>
     </listitem>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2024-08-04 [7949d9594] Introduce pluggable APIs for Cumulative Statistics
Author: Michael Paquier <michael@paquier.xyz>
2024-08-05 [2eff9e678] Add helper routines to retrieve data for custom fixed-nu
-->

     <listitem>
     <para>
     Allow extensions to use the server's cumulative statistics
     <acronym>API</acronym> (Michael Paquier)
     <ulink url="&commit_baseurl;7949d9594">&sect;</ulink>
     <ulink url="&commit_baseurl;2eff9e678">&sect;</ulink>
     </para>
     </listitem>

    </itemizedlist>

    <sect4 id="release-18-pgstatstatements">
     <title><xref linkend="pgstatstatements"/></title>

     <itemizedlist>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2024-10-28 [6b652e6ce] Set query ID for inner queries of CREATE TABLE AS and DE
-->

      <listitem>
      <para>
      Allow the queries of <xref linkend="sql-createtableas"/>
      and <xref linkend="sql-declare"/> to be tracked by
      <application>pg_stat_statements</application> (Anthonin Bonnefoy)
      <ulink url="&commit_baseurl;6b652e6ce">&sect;</ulink>
      </para>

      <para>
      They are also now assigned query ids.
      </para>
      </listitem>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2024-09-30 [dc6851596] Show values of SET statements as constants in pg_stat_st
-->

      <listitem>
      <para>
      Allow the parameterization of <xref linkend="sql-set"/> values in
      <application>pg_stat_statements</application> (Greg Sabino Mullane,
      Michael Paquier)
      <ulink url="&commit_baseurl;dc6851596">&sect;</ulink>
      </para>

      <para>
      This reduces the bloat caused by <command>SET</command> statements
      with differing constants.
      </para>
      </listitem>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2024-10-09 [cf54a2c00] pg_stat_statements: Add columns to track parallel worker
-->

      <listitem>
      <para>
      Add <link
      linkend="pgstatstatements-pg-stat-statements"><structname>pg_stat_statements</structname></link>
      columns to report parallel activity (Guillaume Lelarge)
      <ulink url="&commit_baseurl;cf54a2c00">&sect;</ulink>
      </para>

      <para>
      The new columns are
      <structfield>parallel_workers_to_launch</structfield> and
      <structfield>parallel_workers_launched</structfield>.
      </para>
      </listitem>

<!--
Author: Michael Paquier <michael@paquier.xyz>
2025-02-17 [ce5bcc4a9] pg_stat_statements: Add wal_buffers_full
-->

      <listitem>
      <para>
      Add
      <structname>pg_stat_statements</structname>.<structfield>wal_buffers_full</structfield>
      to report full <acronym>WAL</acronym> buffers (Bertrand Drouvot)
      <ulink url="&commit_baseurl;ce5bcc4a9">&sect;</ulink>
      </para>
      </listitem>

     </itemizedlist>

    </sect4>

    <sect4 id="release-18-pgcrypto">
     <title><xref linkend="pgcrypto"/></title>

     <itemizedlist>

<!--
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
2025-04-05 [749a9e20c] Add modern SHA-2 based password hashes to pgcrypto.
-->

      <listitem>
      <para>
      Add <application>pgcrypto</application> algorithms <link
      linkend="pgcrypto-crypt-algorithms"><literal>sha256crypt</literal></link>
      and <link
      linkend="pgcrypto-crypt-algorithms"><literal>sha512crypt</literal></link>
      (Bernd Helmle)
      <ulink url="&commit_baseurl;749a9e20c">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Daniel Gustafsson <dgustafsson@postgresql.org>
2025-02-14 [9ad1b3d01] pgcrypto: Add support for CFB mode in AES encryption
-->

      <listitem>
      <para>
      Add <link
      linkend="pgcrypto-raw-enc-funcs"><acronym>CFB</acronym></link> mode
      to <application>pgcrypto</application> encryption and decryption
      (Umar Hayat)
      <ulink url="&commit_baseurl;9ad1b3d01">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Daniel Gustafsson <dgustafsson@postgresql.org>
2025-01-24 [924d89a35] pgcrypto: Add function to check FIPS mode
-->

      <listitem>
      <para>
      Add function <link
      linkend="pgcrypto-openssl-support-funcs"><function>fips_mode()</function></link>
      to report the server's <acronym>FIPS</acronym> mode (Daniel
      Gustafsson)
      <ulink url="&commit_baseurl;924d89a35">&sect;</ulink>
      </para>
      </listitem>

<!--
Author: Daniel Gustafsson <dgustafsson@postgresql.org>
2025-01-24 [035f99cbe] pgcrypto: Make it possible to disable built-in crypto
-->

      <listitem>
      <para>
      Add <application>pgcrypto</application> server variable <link
      linkend="pgcrypto-configuration-parameters-builtin_crypto_enabled"><varname>builtin_crypto_enabled</varname></link>
      to allow disabling builtin non-<acronym>FIPS</acronym> mode
      cryptographic functions (Daniel Gustafsson, Joe Conway)
      <ulink url="&commit_baseurl;035f99cbe">&sect;</ulink>
      </para>

      <para>
      This is useful for guaranteeing <acronym>FIPS</acronym> mode behavior.
      </para>
      </listitem>

     </itemizedlist>
    </sect4>

   </sect3>

  </sect2>

  <sect2 id="release-18-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>(to be completed)</member>
   </simplelist>
  </sect2>

 </sect1>
