Specifying empty tag style

Question

Hi all. I'm using dbms_xmlquery.useNullAttributeIndicator, and for a reason I'd rather not go into I need the tags to be separate open-close tags (<tag></tag>) instead of the more elegant <tag/> tag. I'd also like to suppress the NULL="TRUE" attribute if possible. I'm open to changing our routine to use DBMS_XMLGEN if it helps in the above. Many thanks in advance for your help.

Answer 1

Hi,
With DBMS_XMLGEN, you can get rid of the NULL attribute, but empty tags will appear in the short form :
SQL> set serveroutput on
SQL> DECLARE
  2    ctx    dbms_xmlgen.ctxHandle;
  3    sqlstr varchar2(4000) := 'SELECT * FROM scott.emp WHERE rownum = 1';
  4    res    clob;
  5  BEGIN
  6    ctx := dbms_xmlgen.newContext(sqlstr);
  7    dbms_xmlgen.setNullHandling(ctx, dbms_xmlgen.EMPTY_TAG);
  8    res := dbms_xmlgen.getXML(ctx);
  9    dbms_xmlgen.closeContext(ctx);
10    dbms_output.put_line(res);
11  END;
12  /
<?xml version="1.0"?>
<ROWSET>
<ROW>
  <EMPNO>7369</EMPNO>
  <ENAME>SMITH</ENAME>
  <JOB>CLERK</JOB>
  <MGR>7902</MGR>
  <HIREDATE>17/12/80</HIREDATE>
  <SAL>800</SAL>
  <COMM/>
  <DEPTNO>20</DEPTNO>
</ROW>
</ROWSET>
PL/SQL procedure successfully completed
On the latest release (11.2), and only for particular cases, you might be able to do what you want with XQuery.
See § Oracle XQuery Extension-Expression Pragmas on this page :
http://download.oracle.com/docs/cd/E11882_01/appdev.112/e16659/xdb_xquery.htm
Here's also an example :
SELECT XMLSerialize(
document
XMLQuery(
  '(#ora:view_on_null empty #)
   <ROWSET>
    for $i in fn:collection("oradb:/SCOTT/EMP")/ROW
    where $i/EMPNO = 7566
    return $i
   </ROWSET>
  returning content
as clob
FROM dual;
<ROWSET><ROW><EMPNO>7566</EMPNO><ENAME>JONES</ENAME><JOB>MANAGER</JOB><MGR>7839</MGR><HIREDATE>1981-04-02</HIREDATE><SAL>2975</SAL><COMM></COMM><DEPTNO>20</DEPTNO></ROW></ROWSET>