Clarify NULLIF example

found by "Vesa-Matti J Kari" <vmkari@cc.helsinki.fi>

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 3f2fe80f5a4f00d7d0644880f8b7fbc377d6046d..df6dbf379fa108f662aa8206c75c96396afd3946 100644 (file)
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -9193,8 +9193,9 @@ SELECT NULLIF(value, '(none)') ...
 </programlisting>
   </para>
   <para>
-   If <replaceable>value1</replaceable> is <literal>(none)</>, return a null,
-   otherwise return <replaceable>value1</replaceable>.
+   In this example, if <literal>value</literal> is <literal>(none)</>,
+   null is returned, otherwise the value of <literal>value</literal>
+   is returned.
   </para>
 
   </sect2>