<!--
-$PostgreSQL: pgsql/doc/src/sgml/ref/create_function.sgml,v 1.57 2004/06/25 07:05:34 dennis Exp $
+$PostgreSQL: pgsql/doc/src/sgml/ref/create_function.sgml,v 1.58 2004/07/11 23:23:43 momjian Exp $
-->
<refentry id="SQL-CREATEFUNCTION">
LANGUAGE SQL
IMMUTABLE
RETURNS NULL ON NULL INPUT;
+</programlisting>
+ </para>
+
+ <para>
+ Increment an integer, making use of an argument name, in PL/PgSQL:
+
+<programlisting>
+CREATE OR REPLACE FUNCTION increment(i integer) RETURNS integer AS '
+ BEGIN
+ RETURN i + 1;
+ END;' LANGUAGE plpgsql;
</programlisting>
</para>
</refsect1>