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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>VACUUM</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><link rel="prev" href="sql-update.html" title="UPDATE" /><link rel="next" href="sql-values.html" title="VALUES" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">VACUUM</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="sql-update.html" title="UPDATE">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="sql-commands.html" title="SQL Commands">Up</a></td><th width="60%" align="center">SQL Commands</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 18.4 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="sql-values.html" title="VALUES">Next</a></td></tr></table><hr /></div><div class="refentry" id="SQL-VACUUM"><div class="titlepage"></div><a id="id-1.9.3.184.1" class="indexterm"></a><div class="refnamediv"><h2><span class="refentrytitle">VACUUM</span></h2><p>VACUUM — garbage-collect and optionally analyze a database</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><pre class="synopsis">
VACUUM [ ( <em class="replaceable"><code>option</code></em> [, ...] ) ] [ <em class="replaceable"><code>table_and_columns</code></em> [, ...] ]

<span class="phrase">where <em class="replaceable"><code>option</code></em> can be one of:</span>

    FULL [ <em class="replaceable"><code>boolean</code></em> ]
    FREEZE [ <em class="replaceable"><code>boolean</code></em> ]
    VERBOSE [ <em class="replaceable"><code>boolean</code></em> ]
    ANALYZE [ <em class="replaceable"><code>boolean</code></em> ]
    DISABLE_PAGE_SKIPPING [ <em class="replaceable"><code>boolean</code></em> ]
    SKIP_LOCKED [ <em class="replaceable"><code>boolean</code></em> ]
    INDEX_CLEANUP { AUTO | ON | OFF }
    PROCESS_MAIN [ <em class="replaceable"><code>boolean</code></em> ]
    PROCESS_TOAST [ <em class="replaceable"><code>boolean</code></em> ]
    TRUNCATE [ <em class="replaceable"><code>boolean</code></em> ]
    PARALLEL <em class="replaceable"><code>integer</code></em>
    SKIP_DATABASE_STATS [ <em class="replaceable"><code>boolean</code></em> ]
    ONLY_DATABASE_STATS [ <em class="replaceable"><code>boolean</code></em> ]
    BUFFER_USAGE_LIMIT <em class="replaceable"><code>size</code></em>

<span class="phrase">and <em class="replaceable"><code>table_and_columns</code></em> is:</span>

    [ ONLY ] <em class="replaceable"><code>table_name</code></em> [ * ] [ ( <em class="replaceable"><code>column_name</code></em> [, ...] ) ]
</pre></div><div class="refsect1" id="id-1.9.3.184.5"><h2>Description</h2><p>
   <code class="command">VACUUM</code> reclaims storage occupied by dead tuples.
   In normal <span class="productname">PostgreSQL</span> operation, tuples that
   are deleted or obsoleted by an update are not physically removed from
   their table; they remain present until a <code class="command">VACUUM</code> is
   done.  Therefore it's necessary to do <code class="command">VACUUM</code>
   periodically, especially on frequently-updated tables.
  </p><p>
   Without a <em class="replaceable"><code>table_and_columns</code></em>
   list, <code class="command">VACUUM</code> processes every table and materialized view
   in the current database that the current user has permission to vacuum.
   With a list, <code class="command">VACUUM</code> processes only those table(s).
  </p><p>
   <code class="command">VACUUM ANALYZE</code> performs a <code class="command">VACUUM</code>
   and then an <code class="command">ANALYZE</code> for each selected table.  This
   is a handy combination form for routine maintenance scripts.  See
   <a class="xref" href="sql-analyze.html" title="ANALYZE"><span class="refentrytitle">ANALYZE</span></a>
   for more details about its processing.
  </p><p>
   Plain <code class="command">VACUUM</code> (without <code class="literal">FULL</code>) simply reclaims
   space and makes it
   available for re-use.  This form of the command can operate in parallel
   with normal reading and writing of the table, as an exclusive lock
   is not obtained.  However, extra space is not returned to the operating
   system (in most cases); it's just kept available for re-use within the
   same table.  It also allows us to leverage multiple CPUs in order to process
   indexes.  This feature is known as <em class="firstterm">parallel vacuum</em>.
   To disable this feature, one can use <code class="literal">PARALLEL</code> option and
   specify parallel workers as zero.  <code class="command">VACUUM FULL</code> rewrites
   the entire contents of the table into a new disk file with no extra space,
   allowing unused space to be returned to the operating system.  This form is
   much slower and requires an <code class="literal">ACCESS EXCLUSIVE</code> lock on
   each table while it is being processed.
  </p></div><div class="refsect1" id="id-1.9.3.184.6"><h2>Parameters</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><code class="literal">FULL</code></span></dt><dd><p>
      Selects <span class="quote">“<span class="quote">full</span>”</span> vacuum, which can reclaim more
      space, but takes much longer and exclusively locks the table.
      This method also requires extra disk space, since it writes a
      new copy of the table and doesn't release the old copy until
      the operation is complete.  Usually this should only be used when a
      significant amount of space needs to be reclaimed from within the table.
     </p></dd><dt><span class="term"><code class="literal">FREEZE</code></span></dt><dd><p>
      Selects aggressive <span class="quote">“<span class="quote">freezing</span>”</span> of tuples.
      Specifying <code class="literal">FREEZE</code> is equivalent to performing
      <code class="command">VACUUM</code> with the
      <a class="xref" href="runtime-config-vacuum.html#GUC-VACUUM-FREEZE-MIN-AGE">vacuum_freeze_min_age</a> and
      <a class="xref" href="runtime-config-vacuum.html#GUC-VACUUM-FREEZE-TABLE-AGE">vacuum_freeze_table_age</a> parameters
      set to zero.  Aggressive freezing is always performed when the
      table is rewritten, so this option is redundant when <code class="literal">FULL</code>
      is specified.
     </p></dd><dt><span class="term"><code class="literal">VERBOSE</code></span></dt><dd><p>
      Prints a detailed vacuum activity report for each table
      at <code class="literal">INFO</code> level.
     </p></dd><dt><span class="term"><code class="literal">ANALYZE</code></span></dt><dd><p>
      Updates statistics used by the planner to determine the most
      efficient way to execute a query.
     </p></dd><dt><span class="term"><code class="literal">DISABLE_PAGE_SKIPPING</code></span></dt><dd><p>
      Normally, <code class="command">VACUUM</code> will skip pages based on the <a class="link" href="routine-vacuuming.html#VACUUM-FOR-VISIBILITY-MAP" title="24.1.4. Updating the Visibility Map">visibility map</a>.  Pages where
      all tuples are known to be frozen can always be skipped, and those
      where all tuples are known to be visible to all transactions may be
      skipped except when performing an aggressive vacuum.  Furthermore,
      except when performing an aggressive vacuum, some pages may be skipped
      in order to avoid waiting for other sessions to finish using them.
      This option disables all page-skipping behavior, and is intended to
      be used only when the contents of the visibility map are
      suspect, which should happen only if there is a hardware or software
      issue causing database corruption.
     </p></dd><dt><span class="term"><code class="literal">SKIP_LOCKED</code></span></dt><dd><p>
      Specifies that <code class="command">VACUUM</code> should not wait for any
      conflicting locks to be released when beginning work on a relation:
      if a relation cannot be locked immediately without waiting, the relation
      is skipped.  Note that even with this option,
      <code class="command">VACUUM</code> may still block when opening the relation's
      indexes.  Additionally, <code class="command">VACUUM ANALYZE</code> may still
      block when acquiring sample rows from partitions, table inheritance
      children, and some types of foreign tables.  Also, while
      <code class="command">VACUUM</code> ordinarily processes all partitions of
      specified partitioned tables, this option will cause
      <code class="command">VACUUM</code> to skip all partitions if there is a
      conflicting lock on the partitioned table.
     </p></dd><dt><span class="term"><code class="literal">INDEX_CLEANUP</code></span></dt><dd><p>
      Normally, <code class="command">VACUUM</code> will skip index vacuuming
      when there are very few dead tuples in the table.  The cost of
      processing all of the table's indexes is expected to greatly
      exceed the benefit of removing dead index tuples when this
      happens.  This option can be used to force
      <code class="command">VACUUM</code> to process indexes when there are more
      than zero dead tuples.  The default is <code class="literal">AUTO</code>,
      which allows <code class="command">VACUUM</code> to skip index vacuuming
      when appropriate.  If <code class="literal">INDEX_CLEANUP</code> is set to
      <code class="literal">ON</code>, <code class="command">VACUUM</code> will
      conservatively remove all dead tuples from indexes.  This may be
      useful for backwards compatibility with earlier releases of
      <span class="productname">PostgreSQL</span> where this was the
      standard behavior.
     </p><p>
      <code class="literal">INDEX_CLEANUP</code> can also be set to
      <code class="literal">OFF</code> to force <code class="command">VACUUM</code> to
      <span class="emphasis"><em>always</em></span> skip index vacuuming, even when
      there are many dead tuples in the table.  This may be useful
      when it is necessary to make <code class="command">VACUUM</code> run as
      quickly as possible to avoid imminent transaction ID wraparound
      (see <a class="xref" href="routine-vacuuming.html#VACUUM-FOR-WRAPAROUND" title="24.1.5. Preventing Transaction ID Wraparound Failures">Section 24.1.5</a>).  However, the
      wraparound failsafe mechanism controlled by <a class="xref" href="runtime-config-vacuum.html#GUC-VACUUM-FAILSAFE-AGE">vacuum_failsafe_age</a>  will generally trigger
      automatically to avoid transaction ID wraparound failure, and
      should be preferred.  If index cleanup is not performed
      regularly, performance may suffer, because as the table is
      modified indexes will accumulate dead tuples and the table
      itself will accumulate dead line pointers that cannot be removed
      until index cleanup is completed.
     </p><p>
      This option has no effect for tables that have no index and is
      ignored if the <code class="literal">FULL</code> option is used.  It also
      has no effect on the transaction ID wraparound failsafe
      mechanism.  When triggered it will skip index vacuuming, even
      when <code class="literal">INDEX_CLEANUP</code> is set to
      <code class="literal">ON</code>.
     </p></dd><dt><span class="term"><code class="literal">PROCESS_MAIN</code></span></dt><dd><p>
      Specifies that <code class="command">VACUUM</code> should attempt to process the
      main relation. This is usually the desired behavior and is the default.
      Setting this option to false may be useful when it is only necessary to
      vacuum a relation's corresponding <code class="literal">TOAST</code> table.
     </p></dd><dt><span class="term"><code class="literal">PROCESS_TOAST</code></span></dt><dd><p>
      Specifies that <code class="command">VACUUM</code> should attempt to process the
      corresponding <code class="literal">TOAST</code> table for each relation, if one
      exists. This is usually the desired behavior and is the default.
      Setting this option to false may be useful when it is only necessary to
      vacuum the main relation. This option is required when the
      <code class="literal">FULL</code> option is used.
     </p></dd><dt><span class="term"><code class="literal">TRUNCATE</code></span></dt><dd><p>
      Specifies that <code class="command">VACUUM</code> should attempt to
      truncate off any empty pages at the end of the table and allow
      the disk space for the truncated pages to be returned to
      the operating system. This is normally the desired behavior
      and is the default unless <a class="xref" href="runtime-config-vacuum.html#GUC-VACUUM-TRUNCATE">vacuum_truncate</a>
      is set to false or the <code class="literal">vacuum_truncate</code>
      option has been set to false for the table to be vacuumed.
      Setting this option to false may be useful to avoid
      <code class="literal">ACCESS EXCLUSIVE</code> lock on the table that
      the truncation requires. This option is ignored if the
      <code class="literal">FULL</code> option is used.
     </p></dd><dt><span class="term"><code class="literal">PARALLEL</code></span></dt><dd><p>
      Perform index vacuum and index cleanup phases of <code class="command">VACUUM</code>
      in parallel using <em class="replaceable"><code>integer</code></em>
      background workers (for the details of each vacuum phase, please
      refer to <a class="xref" href="progress-reporting.html#VACUUM-PHASES" title="Table 27.46. VACUUM Phases">Table 27.46</a>).  The number of workers used
      to perform the operation is equal to the number of indexes on the
      relation that support parallel vacuum which is limited by the number of
      workers specified with <code class="literal">PARALLEL</code> option if any which is
      further limited by <a class="xref" href="runtime-config-resource.html#GUC-MAX-PARALLEL-MAINTENANCE-WORKERS">max_parallel_maintenance_workers</a>.
      An index can participate in parallel vacuum if and only if the size of the
      index is more than <a class="xref" href="runtime-config-query.html#GUC-MIN-PARALLEL-INDEX-SCAN-SIZE">min_parallel_index_scan_size</a>.
      Please note that it is not guaranteed that the number of parallel workers
      specified in <em class="replaceable"><code>integer</code></em> will be
      used during execution.  It is possible for a vacuum to run with fewer
      workers than specified, or even with no workers at all.  Only one worker
      can be used per index.  So parallel workers are launched only when there
      are at least <code class="literal">2</code> indexes in the table.  Workers for
      vacuum are launched before the start of each phase and exit at the end of
      the phase.  These behaviors might change in a future release.  This
      option can't be used with the <code class="literal">FULL</code> option.
     </p></dd><dt><span class="term"><code class="literal">SKIP_DATABASE_STATS</code></span></dt><dd><p>
      Specifies that <code class="command">VACUUM</code> should skip updating the
      database-wide statistics about oldest unfrozen XIDs.  Normally
      <code class="command">VACUUM</code> will update these statistics once at the
      end of the command.  However, this can take awhile in a database
      with a very large number of tables, and it will accomplish nothing
      unless the table that had contained the oldest unfrozen XID was
      among those vacuumed.  Moreover, if multiple <code class="command">VACUUM</code>
      commands are issued in parallel, only one of them can update the
      database-wide statistics at a time.  Therefore, if an application
      intends to issue a series of many <code class="command">VACUUM</code>
      commands, it can be helpful to set this option in all but the last
      such command; or set it in all the commands and separately
      issue <code class="literal">VACUUM (ONLY_DATABASE_STATS)</code> afterwards.
     </p></dd><dt><span class="term"><code class="literal">ONLY_DATABASE_STATS</code></span></dt><dd><p>
      Specifies that <code class="command">VACUUM</code> should do nothing except
      update the database-wide statistics about oldest unfrozen XIDs.
      When this option is specified,
      the <em class="replaceable"><code>table_and_columns</code></em>
      list must be empty, and no other option may be enabled
      except <code class="literal">VERBOSE</code>.
     </p></dd><dt><span class="term"><code class="literal">BUFFER_USAGE_LIMIT</code></span></dt><dd><p>
      Specifies the
      <a class="glossterm" href="glossary.html#GLOSSARY-BUFFER-ACCESS-STRATEGY"><em class="glossterm"><a class="glossterm" href="glossary.html#GLOSSARY-BUFFER-ACCESS-STRATEGY" title="Buffer Access Strategy">Buffer Access Strategy</a></em></a>
      ring buffer size for <code class="command">VACUUM</code>.  This size is used to
      calculate the number of shared buffers which will be reused as part of
      this strategy.  <code class="literal">0</code> disables use of a
      <code class="literal">Buffer Access Strategy</code>.  If <code class="option">ANALYZE</code>
      is also specified, the <code class="option">BUFFER_USAGE_LIMIT</code> value is used
      for both the vacuum and analyze stages.  This option can't be used with
      the <code class="option">FULL</code> option except if <code class="option">ANALYZE</code> is
      also specified.  When this option is not specified,
      <code class="command">VACUUM</code> uses the value from
      <a class="xref" href="runtime-config-resource.html#GUC-VACUUM-BUFFER-USAGE-LIMIT">vacuum_buffer_usage_limit</a>.  Higher settings can
      allow <code class="command">VACUUM</code> to run more quickly, but having too
      large a setting may cause too many other useful pages to be evicted from
      shared buffers.  The minimum value is <code class="literal">128 kB</code> and the
      maximum value is <code class="literal">16 GB</code>.
     </p></dd><dt><span class="term"><em class="replaceable"><code>boolean</code></em></span></dt><dd><p>
      Specifies whether the selected option should be turned on or off.
      You can write <code class="literal">TRUE</code>, <code class="literal">ON</code>, or
      <code class="literal">1</code> to enable the option, and <code class="literal">FALSE</code>,
      <code class="literal">OFF</code>, or <code class="literal">0</code> to disable it.  The
      <em class="replaceable"><code>boolean</code></em> value can also
      be omitted, in which case <code class="literal">TRUE</code> is assumed.
     </p></dd><dt><span class="term"><em class="replaceable"><code>integer</code></em></span></dt><dd><p>
      Specifies a non-negative integer value passed to the selected option.
     </p></dd><dt><span class="term"><em class="replaceable"><code>size</code></em></span></dt><dd><p>
      Specifies an amount of memory in kilobytes.  Sizes may also be specified
      as a string containing the numerical size followed by any one of the
      following memory units: <code class="literal">B</code> (bytes),
      <code class="literal">kB</code> (kilobytes), <code class="literal">MB</code> (megabytes),
      <code class="literal">GB</code> (gigabytes), or <code class="literal">TB</code> (terabytes).
     </p></dd><dt><span class="term"><em class="replaceable"><code>table_name</code></em></span></dt><dd><p>
      The name (optionally schema-qualified) of a specific table or
      materialized view to vacuum.  If <code class="literal">ONLY</code> is specified
      before the table name, only that table is vacuumed.  If
      <code class="literal">ONLY</code> is not specified, the table and all its
      inheritance child tables or partitions (if any) are also vacuumed.
      Optionally, <code class="literal">*</code> can be specified after the table name
      to explicitly indicate that inheritance child tables (or partitions) are
      to be vacuumed.
     </p></dd><dt><span class="term"><em class="replaceable"><code>column_name</code></em></span></dt><dd><p>
      The name of a specific column to analyze. Defaults to all columns.
      If a column list is specified, <code class="literal">ANALYZE</code> must also be
      specified.
     </p></dd></dl></div></div><div class="refsect1" id="id-1.9.3.184.7"><h2>Outputs</h2><p>
    When <code class="literal">VERBOSE</code> is specified, <code class="command">VACUUM</code> emits
    progress messages to indicate which table is currently being
    processed.  Various statistics about the tables are printed as well.
   </p></div><div class="refsect1" id="id-1.9.3.184.8"><h2>Notes</h2><p>
    To vacuum a table, one must ordinarily have the <code class="literal">MAINTAIN</code>
    privilege on the table.  However, database owners are allowed to
    vacuum all tables in their databases, except shared catalogs.
    <code class="command">VACUUM</code> will skip over any tables that the calling user
    does not have permission to vacuum.
   </p><p>
    While <code class="command">VACUUM</code> is running, the <a class="xref" href="runtime-config-client.html#GUC-SEARCH-PATH">search_path</a> is temporarily changed to <code class="literal">pg_catalog,
    pg_temp</code>.
   </p><p>
    <code class="command">VACUUM</code> cannot be executed inside a transaction block.
   </p><p>
    For tables with <acronym class="acronym">GIN</acronym> indexes, <code class="command">VACUUM</code> (in
    any form) also completes any pending index insertions, by moving pending
    index entries to the appropriate places in the main <acronym class="acronym">GIN</acronym> index
    structure.  See <a class="xref" href="gin.html#GIN-FAST-UPDATE" title="65.4.4.1. GIN Fast Update Technique">Section 65.4.4.1</a> for details.
   </p><p>
    We recommend that all databases be vacuumed regularly in
    order to remove dead rows.  <span class="productname">PostgreSQL</span> includes
    an <span class="quote">“<span class="quote">autovacuum</span>”</span> facility which can automate routine vacuum
    maintenance.  For more information about automatic and manual vacuuming,
    see <a class="xref" href="routine-vacuuming.html" title="24.1. Routine Vacuuming">Section 24.1</a>.
   </p><p>
    The <code class="option">FULL</code> option is not recommended for routine use,
    but might be useful in special cases.  An example is when you have deleted
    or updated most of the rows in a table and would like the table to
    physically shrink to occupy less disk space and allow faster table
    scans. <code class="command">VACUUM FULL</code> will usually shrink the table
    more than a plain <code class="command">VACUUM</code> would.
   </p><p>
     The <code class="option">PARALLEL</code> option is used only for vacuum purposes.
     If this option is specified with the <code class="option">ANALYZE</code> option,
     it does not affect <code class="option">ANALYZE</code>.
   </p><p>
    <code class="command">VACUUM</code> causes a substantial increase in I/O traffic,
    which might cause poor performance for other active sessions.  Therefore,
    it is sometimes advisable to use the cost-based vacuum delay feature.  For
    parallel vacuum, each worker sleeps in proportion to the work done by that
    worker.  See <a class="xref" href="runtime-config-vacuum.html#RUNTIME-CONFIG-RESOURCE-VACUUM-COST" title="19.10.2. Cost-based Vacuum Delay">Section 19.10.2</a> for
    details.
   </p><p>
    Each backend running <code class="command">VACUUM</code> without the
    <code class="literal">FULL</code> option will report its progress in the
    <code class="structname">pg_stat_progress_vacuum</code> view. Backends running
    <code class="command">VACUUM FULL</code> will instead report their progress in the
    <code class="structname">pg_stat_progress_cluster</code> view. See
    <a class="xref" href="progress-reporting.html#VACUUM-PROGRESS-REPORTING" title="27.4.5. VACUUM Progress Reporting">Section 27.4.5</a> and
    <a class="xref" href="progress-reporting.html#CLUSTER-PROGRESS-REPORTING" title="27.4.2. CLUSTER Progress Reporting">Section 27.4.2</a> for details.
   </p></div><div class="refsect1" id="id-1.9.3.184.9"><h2>Examples</h2><p>
   To clean a single table <code class="literal">onek</code>, analyze it for
   the optimizer and print a detailed vacuum activity report:

</p><pre class="programlisting">
VACUUM (VERBOSE, ANALYZE) onek;
</pre></div><div class="refsect1" id="id-1.9.3.184.10"><h2>Compatibility</h2><p>
   There is no <code class="command">VACUUM</code> statement in the SQL standard.
  </p><p>
   The following syntax was used before <span class="productname">PostgreSQL</span>
   version 9.0 and is still supported:
</p><pre class="synopsis">
VACUUM [ FULL ] [ FREEZE ] [ VERBOSE ] [ ANALYZE ] [ <em class="replaceable"><code>table_and_columns</code></em> [, ...] ]
</pre><p>
   Note that in this syntax, the options must be specified in exactly the order
   shown.
  </p></div><div class="refsect1" id="id-1.9.3.184.11"><h2>See Also</h2><span class="simplelist"><a class="xref" href="app-vacuumdb.html" title="vacuumdb"><span class="refentrytitle"><span class="application">vacuumdb</span></span></a>, <a class="xref" href="runtime-config-vacuum.html#RUNTIME-CONFIG-RESOURCE-VACUUM-COST" title="19.10.2. Cost-based Vacuum Delay">Section 19.10.2</a>, <a class="xref" href="routine-vacuuming.html#AUTOVACUUM" title="24.1.6. The Autovacuum Daemon">Section 24.1.6</a>, <a class="xref" href="progress-reporting.html#VACUUM-PROGRESS-REPORTING" title="27.4.5. VACUUM Progress Reporting">Section 27.4.5</a>, <a class="xref" href="progress-reporting.html#CLUSTER-PROGRESS-REPORTING" title="27.4.2. CLUSTER Progress Reporting">Section 27.4.2</a></span></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="sql-update.html" title="UPDATE">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="sql-commands.html" title="SQL Commands">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="sql-values.html" title="VALUES">Next</a></td></tr><tr><td width="40%" align="left" valign="top">UPDATE </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 18.4 Documentation">Home</a></td><td width="40%" align="right" valign="top"> VALUES</td></tr></table></div></body></html>