How can I control creation of empty tags when using ora:view syntax?

Question

I'm using XMLQuery and ora:view syntax to create xml resources in the database but I'd like to be able to prevent the creation of empty tags for null values in the table.
CREATE OR REPLACE PROCEDURE proc_ctsi_build is
XMLdoc XMLType;
BEGIN
DBMS_XDB.deleteResource('/public/CTSI/ctsi_phsall_rpt1.xml',1);
SELECT XMLQuery(
'<Progress_Report>
<Personnel_Roster>
{for $c in ora:view("CTSI_INVEST_SOURCE_V")
    let $username  := $c/ROW/COMMONS_USERNAME/text(),
$expertise  := $c/ROW/AREA_OF_EXPERTISE/text()
     return
  <Investigator>
   <Commons_Username>{$username}</Commons_Username>
<Area_of_Expertise>{$expertise}</Area_of_Expertise>
</Investigator>}
</Personnel_Roster>
</Progress_Report>'
RETURNING CONTENT) INTO XMLdoc FROM DUAL;
IF(DBMS_XDB.CREATERESOURCE('/public/CTSI/ctsi_phsall_rpt1.xml', XMLdoc)) THEN
DBMS_OUTPUT.PUT_LINE('Resource is created');
ELSE
DBMS_OUTPUT.PUT_LINE('Cannot create resource');
END IF;
COMMIT;
END;
In this example how can I prevent getting <Area_of_Expertise/> in my output when AREA_OF_EXPERTISE is null in the table?
Thanks

Answer 1

Hi,
you can use if else conditions.
{if ($expertise) then
<Area_of_Expertise>{$expertise}</Area_of_Expertise>
else ()}
**not tested**
Ants
Message was edited by:
Ants Hindpere