SQL & PL/SQL

Dear subscribers:

I have been using XMLType successfully with simple XMLs - without namespaces. Now I must handle messages with "xmlns" and it seems XMLType is failing.

I tested the following XML, extracted from w3c.org examples:

<?xml version="1.0"?>
<bk:book xmlns:bk=''urn:loc.gov:books''
xmlns:isbn=''urn:ISBN:0-395-36341-6''>
<bk:title>Cheaper by the Dozen</bk:title>
<isbn:number>1568491379</isbn:number>
</bk:book>

The result of “xmlt.getRootElement()” is “book”.
However, the use of “xmlt.extract( 'book' )” returns an empty object:

xmlt1 := xmlt.extract( 'book' );
dbms_output.put_line( 'StringVal: ' || xmlt1.getStringVal() );
ORA-30625: method dispatch on NULL SELF argument is disallowed

The following usages also raise errors:

xmlt1 := xmlt.extract( 'bk:book' );
ORA-31011: XML parsing failed ORA-19202: Error occurred in XML processing LPX-00601: Invalid token in: 'bk:book' ORA-06512: at "SYS.XMLTYPE", line 111

xmlt1 := xmlt.extract( 'bk::book' );
ORA-31011: XML parsing failed ORA-19202: Error occurred in XML processing LPX-00601: Invalid token in: 'bk::book' ORA-06512: at "SYS.XMLTYPE", line 111

xmlt1 := xmlt.extract( 'book', 'bk' );
ORA-31013: Invalid XPATH expression ORA-06512: at "SYS.XMLTYPE", line 119

I am using Oracle version 10.2.0.1.0. Had someone also faced this problem?

The code I used to test is at the end of this message.

Thanks in advance

====================================
DECLARE

xml varchar2(32000);
xmlt XMLType;
xmlt1 XMLType;
root varchar2(3000);

BEGIN

--Example from w3c.org
xml := '<?xml version="1.0"?>
<bk:book xmlns:bk=''urn:loc.gov:books''
xmlns:isbn=''urn:ISBN:0-395-36341-6''>
<bk:title>Cheaper by the Dozen</bk:title>
<isbn:number>1568491379</isbn:number>
</bk:book>';

xmlt := XMLType( xml );
root := xmlt.getRootElement();
dbms_output.put_line( 'StringVal: ' || xmlt.getStringVal() ); -- The XML is ok…
dbms_output.put_line( 'Namespace: ' || xmlt.getNameSpace() ); -- Returns NULL
dbms_output.put_line( 'Root element: ' || root ); -- Returns ‘book’
dbms_output.put_line( 'Exists: ' || xmlt.existsNode('book') ); -- Returns ZERO

xmlt1 := xmlt.extract( 'bk:book' ); Raises error (see above)
xmlt1 := xmlt.extract( 'bk::book' ); Raises error (see above)
xmlt1 := xmlt.extract( 'book', 'bk' ); Raises error (see above)

--xmlt1 := xmlt.extract( 'book' );
dbms_output.put_line( 'StringVal: ' || xmlt1.getStringVal() ); Raises error

END;
/