Querying attributes from XML

Question

I have Oracle 10g . In a table with just one record there is a a clob with the following xml.
<container>
<param name="paramA" value="valueA" />
<param name="paramB" value="valueB" />
</container>
How can I enumerate paramA, paramB from above?

Answer 1

Your query neglected to show the error message you were getting, which should have been
select x.paramName, x.paramValue
  from test_xml t
     , xmltable('/container/param'
                passing xmltype(t.xmlcontent)
                columns
                paramName varchar2(30) path '@type'
              , paramValue varchar2(80) path '@value') x
ORA-31011: XML parsing failed
ORA-19202: Error occurred in XML processing
LPX-00234: namespace prefix "xsi" is not declared
Error at line 2
ORA-06512: at "SYS.XMLTYPE", line 254
ORA-06512: at line 1Taking that, you would ask yourself how to declare the namespace and some searching would eventually turn up that
1) your sample XML is invalid as it does not have a namespace prefix defined for xsi
2) You need to use XMLNamespaces within the [url http://docs.oracle.com/cd/B19306_01/server.102/b14200/functions228.htm#SQLRF06232]XMLTable function
Putting those together and assuming you mean the standard URI for the xsi prefix, your sample XML should look like
<container xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
     <param xsi:type="paramA" value="valueA"/>
     <param xsi:type="paramB" value="valueB"/>
</container>and the query would look like
select x.paramName, x.paramValue
  from test_xml t
     , xmltable(XMLNamespaces('http://www.w3.org/2001/XMLSchema-instance' as "xsi"),
               '/container/param'
                passing xmltype(t.xmlcontent)
                columns
                paramName varchar2(30) path '@xsi:type'
              , paramValue varchar2(80) path '@value') x;