Select XML with XMLFOREST into CLOB

Question

Hi,
i am trying to select a XMLFOREST expression into a table with a clob column using oracle 10.2.0.4.0.
The query "select xmlforest(e.last_name) from employees e where e.employee_id = 100" returns <LAST_NAME>King</LAST_NAME>. The result is returned as a clob, but i get an error (ora-06550 inconsistent datatypes) if i try to select the query result into a clob.
So i wrote this code fragment to insert the result:
DECLARE
  cl CLOB := NULL;
  chCTX DBMS_XMLGEN.CTXHANDLE;
BEGIN
  chCTX :=  dbms_xmlgen.newContext ('SELECT XMLFOREST(e.last_name)  FROM employees e WHERE e.employee_id = 100');
  dbms_xmlgen.getxml(chCTX,cl );
  INSERT INTO TEMP_XML_CLOB(XML_CLOB)VALUES(cl);
  COMMIT;
END;The plsql block is executed without an error but and inserts a row in the table, but the clob contains no data. So please give me advice how to store the result set in a clob in a proper way.
Thanks in advance
Matthias

Answer 1

Do you really need to store it as a CLOB? Oracle provides an XMLTYPE for storing XML which is far better.
Try using XMLTYPE and something like:
DECLARE
  xml XMLTYPE;
BEGIN
  SELECT XMLFOREST(e.last_name)
  INTO xml
  FROM employees e
  WHERE e.employee_id = 100;
   INSERT INTO TEMP_XML(XML) VALUES (xml);
  COMMIT;
END;(untested)
Obviously you'll want to expand on the SELECT statement to ensure you get all the tags you want and your table will need changing too to cater for XMLTYPE.
I won't ask why you've got a table called "TEMP...", you must know that's just wrong in so many ways.