locale and encoding) that they had in the source cluster.
   Without the option, those databases will retain their existing
   database-level properties, as well as any pre-existing contents.
  </para>

  <para>
   If <option>--with-statistics</option> is specified,
   <command>pg_dumpall</command> will include most optimizer statistics in the
   resulting dump file.  However, some statistics may not be included, such as
   those created explicitly with <xref linkend="sql-createstatistics"/> or
   custom statistics added by an extension.  Therefore, it may be useful to
   run <command>ANALYZE</command> on each database after restoring from a dump
   file to ensure optimal performance.  You can also run <command>vacuumdb -a
   -z</command> to analyze all databases.
  </para>

  <para>
   The dump script should not be expected to run completely without errors.
   In particular, because the script will issue <command>CREATE ROLE</command>
   for every role existing in the source cluster, it is certain to get a
   <quote>role already exists</quote> error for the bootstrap superuser,
   unless the destination cluster was initialized with a different bootstrap
   superuser name.  This error is harmless and should be ignored.  Use of
   the <option>--clean</option> option is likely to produce additional
   harmless error messages about non-existent objects, although you can
   minimize those by adding <option>--if-exists</option>.
  </para>

  <para>
   <application>pg_dumpall</application> requires all needed
   tablespace directories to exist before the restore;  otherwise,
   database creation will fail for databases in non-default
   locations.
  </para>

  <para>
   It is generally recommended to use the <option>-X</option>
   (<option>--no-psqlrc</option>) option when restoring a database from a
   <application>pg_dumpall</application> script to ensure a clean restore
   process and prevent potential conflicts with non-default
   <application>psql</application> configurations. Additionally, because
   the <application>pg_dumpall</application> script may
   include <application>psql</application> meta-commands, it may be
   incompatible with clients other than <application>psql</application>.
  </para>
 </refsect1>


 <refsect1 id="app-pg-dumpall-ex">
  <title>Examples</title>
  <para>
   To dump all databases:

<screen>
<prompt>$</prompt> <userinput>pg_dumpall &gt; db.out</userinput>
</screen>
  </para>

  <para>
   To restore database(s) from this file, you can use:
<screen>
<prompt>$</prompt> <userinput>psql -X -f db.out -d postgres</userinput>
</screen>
   It is not important which database you connect to here since the
   script file created by <application>pg_dumpall</application> will
   contain the appropriate commands to create and connect to the saved
   databases.  An exception is that if you specified <option>--clean</option>,
   you must connect to the <literal>postgres</literal> database initially;
   the script will attempt to drop other databases immediately, and that
   will fail for the database you are connected to.
  </para>
 </refsect1>

 <refsect1>
  <title>See Also</title>

  <para>
    Check <xref linkend="app-pgdump"/> for details on possible
    error conditions.
  </para>
 </refsect1>

</refentry>