linkend="sql-analyze"><command>ANALYZE</command></link>, and a few DDL commands such as
       <link linkend="sql-createindex"><command>CREATE INDEX</command></link>.
      </para></entry>
     </row>

     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       <structfield>reltuples</structfield> <type>float4</type>
      </para>
      <para>
       Number of live rows in the table.  This is only an estimate used by
       the planner.  It is updated by <link linkend="sql-vacuum"><command>VACUUM</command></link>,
       <link linkend="sql-analyze"><command>ANALYZE</command></link>, and a few DDL commands such as
       <link linkend="sql-createindex"><command>CREATE INDEX</command></link>.
       If the table has never yet been vacuumed or
       analyzed, <structfield>reltuples</structfield>
       contains <literal>-1</literal> indicating that the row count is
       unknown.
      </para></entry>
     </row>

     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       <structfield>relallvisible</structfield> <type>int4</type>
      </para>
      <para>
       Number of pages that are marked all-visible in the table's
       visibility map.  This is only an estimate used by the
       planner.  It is updated by <link linkend="sql-vacuum"><command>VACUUM</command></link>,
       <link linkend="sql-analyze"><command>ANALYZE</command></link>, and a few DDL commands such as
       <link linkend="sql-createindex"><command>CREATE INDEX</command></link>.
      </para></entry>
     </row>

     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       <structfield>relallfrozen</structfield> <type>int4</type>
      </para>
      <para>
       Number of pages that are marked all-frozen in the table's visibility
       map.  This is only an estimate used for triggering autovacuums. It can
       also be used along with <structfield>relallvisible</structfield> for
       scheduling manual vacuums and tuning <link
       linkend="runtime-config-vacuum-freezing">vacuum's freezing
       behavior</link>.

       It is updated by
       <link linkend="sql-vacuum"><command>VACUUM</command></link>,
       <link linkend="sql-analyze"><command>ANALYZE</command></link>,
       and a few DDL commands such as
       <link linkend="sql-createindex"><command>CREATE INDEX</command></link>.
      </para></entry>
     </row>


     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       <structfield>reltoastrelid</structfield> <type>oid</type>
       (references <link linkend="catalog-pg-class"><structname>pg_class</structname></link>.<structfield>oid</structfield>)
      </para>
      <para>
       OID of the TOAST table associated with this table, zero if none.  The
       TOAST table stores large attributes <quote>out of line</quote> in a
       secondary table.
      </para></entry>
     </row>

     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       <structfield>relhasindex</structfield> <type>bool</type>
      </para>
      <para>
       True if this is a table and it has (or recently had) any indexes
      </para></entry>
     </row>

     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       <structfield>relisshared</structfield> <type>bool</type>
      </para>
      <para>
       True if this table is shared across all databases in the cluster.  Only
       certain system catalogs (such as <link linkend="catalog-pg-database"><structname>pg_database</structname></link>)
       are shared.
      </para></entry>
     </row>

     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       <structfield>relpersistence</structfield> <type>char</type>
      </para>
      <para>
       <literal>p</literal> = permanent table/sequence, <literal>u</literal> = unlogged table/sequence,
       <literal>t</literal> = temporary table/sequence
      </para></entry>