Fix function name.

doc/src/sgml/release.sgml

 <!--
-$PostgreSQL: pgsql/doc/src/sgml/release.sgml,v 1.348 2005/08/23 20:48:45 momjian Exp $
+$PostgreSQL: pgsql/doc/src/sgml/release.sgml,v 1.349 2005/08/23 20:51:27 momjian Exp $
 -->
 
 <appendix id="release">
@@ -1078,7 +1078,7 @@ $PostgreSQL: pgsql/doc/src/sgml/release.sgml,v 1.348 2005/08/23 20:48:45 momjian
         </itemizedlist>
        </para>
        <para>
-        <function>complete_relation_size()</> includes indexes and TOAST
+        <function>pg_complete_relation_size()</> includes indexes and TOAST
         tables.
        </para>
       </listitem>