</para>
      <para>
       Applies to a feature not available
       in <productname>PostgreSQL</productname>
       (see <literal>datetime_precision</literal> for the fractional
       seconds precision of interval type domains)
      </para></entry>
     </row>

     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       <structfield>domain_default</structfield> <type>character_data</type>
      </para>
      <para>
       Default expression of the domain
      </para></entry>
     </row>

     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       <structfield>udt_catalog</structfield> <type>sql_identifier</type>
      </para>
      <para>
       Name of the database that the domain data type is defined in (always the current database)
      </para></entry>
     </row>

     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       <structfield>udt_schema</structfield> <type>sql_identifier</type>
      </para>
      <para>
       Name of the schema that the domain data type is defined in
      </para></entry>
     </row>

     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       <structfield>udt_name</structfield> <type>sql_identifier</type>
      </para>
      <para>
       Name of the domain data type
      </para></entry>
     </row>

     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       <structfield>scope_catalog</structfield> <type>sql_identifier</type>
      </para>
      <para>
       Applies to a feature not available in <productname>PostgreSQL</productname>
      </para></entry>
     </row>

     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       <structfield>scope_schema</structfield> <type>sql_identifier</type>
      </para>
      <para>
       Applies to a feature not available in <productname>PostgreSQL</productname>
      </para></entry>
     </row>

     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       <structfield>scope_name</structfield> <type>sql_identifier</type>
      </para>
      <para>
       Applies to a feature not available in <productname>PostgreSQL</productname>
      </para></entry>
     </row>

     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       <structfield>maximum_cardinality</structfield> <type>cardinal_number</type>
      </para>
      <para>
       Always null, because arrays always have unlimited maximum cardinality in <productname>PostgreSQL</productname>
      </para></entry>
     </row>

     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       <structfield>dtd_identifier</structfield> <type>sql_identifier</type>
      </para>
      <para>
       An identifier of the data type descriptor of the domain, unique
       among the data type descriptors pertaining to the domain (which
       is trivial, because a domain only contains one data type
       descriptor).  This is mainly useful for joining with other
       instances of such identifiers.  (The specific format of the
       identifier is not defined and not guaranteed to remain the same
       in future versions.)
      </para></entry>
     </row>
    </tbody>
   </tgroup>
  </table>
 </sect1>

 <sect1 id="infoschema-element-types">
  <title><literal>element_types</literal></title>

  <para>
   The view <literal>element_types</literal> contains the data type
   descriptors of the elements of arrays.  When a table column, composite-type attribute,
   domain, function parameter, or function return value is defined to
   be of an array type, the respective information schema view only
   contains <literal>ARRAY</literal> in the column
   <literal>data_type</literal>.  To obtain information on the element
   type of the array, you can join the respective view with this view.
   For example, to show the columns of a table with data types and