DBMS_XMLGEN --Number of active cursors in increased in Exception block

Question

Hi ,
We have a custom code that use DBMS_XMLGEN,the issue is when any exception happens the Number os active cusrors increse and when it happens in a lopp we hit 1000ORA-01000: maximum open cursors exceeded.
Although I close the context in the exception Block.
Below is sample code where I could replicate this:
Step1.Create a table
CREATE TABLE EMP(EMP_NO NUMBER,EMPNAME VARCHAR2(100));
Step2:
Create  a Procedure:
CREATE OR REPLACE PROCEDURE TEST_XMLGEN
AS
l_clob CLOB;
  l_ctx         dbms_xmlgen.ctxhandle;
  p_sql VARCHAR2(4000):='SELECT EMP_NO,,EMPNAME FROM EMP';--syntax error on purpose ,so that exception happens
  l_cursor_count NUMBER;
BEGIN
SELECT VALUE
           INTO l_cursor_count
           FROM v$mystat a, v$statname b
          WHERE     a.statistic# = b.statistic#
                AND b.name = 'opened cursors current';
        DBMS_OUTPUT.PUT_LINE ('open cursors place00' || l_cursor_count);
l_ctx := dbms_xmlgen.newcontext (p_sql);
SELECT VALUE
           INTO l_cursor_count
           FROM v$mystat a, v$statname b
          WHERE     a.statistic# = b.statistic#
                AND b.name = 'opened cursors current';
         DBMS_OUTPUT.PUT_LINE('open cursors place01' || l_cursor_count);
dbms_xmlgen.getxml (l_ctx,l_clob);
SELECT VALUE
           INTO l_cursor_count
           FROM v$mystat a, v$statname b
          WHERE     a.statistic# = b.statistic#
                AND b.name = 'opened cursors current';
         DBMS_OUTPUT.PUT_LINE ('open cursors place02' || l_cursor_count);
DBMS_OUTPUT.PUT_LINE('l_clob:'||l_clob);
dbms_xmlgen.closecontext (l_ctx);
SELECT VALUE
           INTO l_cursor_count
           FROM v$mystat a, v$statname b
          WHERE     a.statistic# = b.statistic#
                AND b.name = 'opened cursors current';
         DBMS_OUTPUT.PUT_LINE ('open cursors place03' || l_cursor_count);
EXCEPTION
WHEN OTHERS
THEN
SELECT VALUE
           INTO l_cursor_count
           FROM v$mystat a, v$statname b
          WHERE     a.statistic# = b.statistic#
                AND b.name = 'opened cursors current';
         DBMS_OUTPUT.PUT_LINE ('open cursors place04' || l_cursor_count);
dbms_xmlgen.closecontext (l_ctx);
SELECT VALUE
           INTO l_cursor_count
           FROM v$mystat a, v$statname b
          WHERE     a.statistic# = b.statistic#
                AND b.name = 'opened cursors current';
         DBMS_OUTPUT.PUT_LINE ('open cursors place05' || l_cursor_count);
END;
Step3: Execute above Procedure
If you look at the number of active cursor it is increased in exception block,I suspect this is what is causing issue with my program too.Any suggestions to solve this issue.
Thanks
Shefali

Answer 1

Did you mean this test:
declare
  ts timestamp;
  type tp_strings is table of varchar2(32767) index by pls_integer;
  t_strings tp_strings;
  t_tmp xmltype;
  t_nd dbms_xmldom.domnode;
  t_nl dbms_xmldom.domnodelist;
  t_clob clob;
begin
  t_clob := '<?xml version="1.0" encoding="UTF-8" standalone="yes"?>'
         || '<sst xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main" count="5000" uniqueCount="5000">';
  for i in 1 .. 5000
  loop
    t_clob := t_clob || to_clob( '<si><t>A' || to_char( i ) || '</t></si>' );
  end loop;
  t_clob := t_clob || '</sst>';
  t_tmp := xmltype( t_clob );
  t_strings.delete;
  ts := systimestamp;
      select str
      bulk collect into t_strings
      from xmltable( xmlnamespaces( default 'http://schemas.openxmlformats.org/spreadsheetml/2006/main' )
                   , '/sst/si' passing t_tmp
                   columns str clob path 't'
  dbms_output.put_line( systimestamp - ts );
  dbms_output.put_line( t_strings.count() || ' ' || t_strings( t_strings.first )  || ' ' || t_strings( t_strings.last ) );
  t_strings.delete;
  ts := systimestamp;
      select /*+ NO_XML_QUERY_REWRITE */ str
      bulk collect into t_strings
      from xmltable( xmlnamespaces( default 'http://schemas.openxmlformats.org/spreadsheetml/2006/main' )
                   , '/sst/si' passing t_tmp
                   columns str clob path 't'
  dbms_output.put_line( systimestamp - ts );
  dbms_output.put_line( t_strings.count() || ' ' || t_strings( t_strings.first )  || ' ' || t_strings( t_strings.last ) );
  t_strings.delete;
  ts := systimestamp;
      t_nd := dbms_xmldom.makenode( dbms_xmldom.getdocumentelement( dbms_xmldom.newdomdocument( t_tmp ) ) );
      t_nl := dbms_xslprocessor.selectnodes( t_nd, '/sst/si/t/text()', 'xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main"' );
      for i in 0 .. dbms_xmldom.getlength( t_nl ) - 1
      loop
        t_strings( i ) := dbms_xmldom.getnodevalue( dbms_xmldom.item( t_nl, i ) );
      end loop;
  dbms_output.put_line( systimestamp - ts );
  dbms_output.put_line( t_strings.count() || ' ' || t_strings( t_strings.first )  || ' ' || t_strings( t_strings.last ) );
end;