1- <!-- $PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.520 2010/06/29 22:29:13 momjian Exp $ -->
1+ <!-- $PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.521 2010/07/03 17:21:48 momjian Exp $ -->
22
33 <chapter id="functions">
44 <title>Functions and Operators</title>
@@ -8610,8 +8610,11 @@ SELECT xmlagg(x) FROM (SELECT * FROM test ORDER BY y DESC) AS tab;
86108610 mappings. This array should be a two-dimensional array with the
86118611 length of the second axis being equal to 2 (i.e., it should be an
86128612 array of arrays, each of which consists of exactly 2 elements).
8613- The first element of each array entry is the namespace name, the
8614- second the namespace URI.
8613+ The first element of each array entry is the namespace name (alias), the
8614+ second the namespace URI. It is not required that aliases provided in
8615+ this array are the same that those being used in the XML document itself (in
8616+ other words, both in the XML document and in the <function>xpath</function>
8617+ function context, aliases are <emphasis>local</>).
86158618 </para>
86168619
86178620 <para>
@@ -8624,6 +8627,19 @@ SELECT xpath('/my:a/text()', '<my:a xmlns:my="http://example.com">test</my:a>',
86248627--------
86258628 {test}
86268629(1 row)
8630+ ]]></screen>
8631+ </para>
8632+
8633+ <para>
8634+ How to deal with default (anonymous) namespaces:
8635+ <screen><![CDATA[
8636+ SELECT xpath('//mydefns:b/text()', '<a xmlns="http://example.com"><b>test</b></a>',
8637+ ARRAY[ARRAY['mydefns', 'http://example.com']]);
8638+
8639+ xpath
8640+ --------
8641+ {test}
8642+ (1 row)
86278643]]></screen>
86288644 </para>
86298645 </sect2>