>> I plan on activating sys 10046 trace, to find a problem that occurs late >> at night. Hi Yechiel, If this is 10g *and* the application uses DBMS_APPLICATION_INFO to set Module/Program/Action or the Client_ID, you can always use DBMS_MONITOR to selectively start the trace. Is this a Connection Pooled instance? That will also change the way trace would work as it would be difficult to detect *which* session is executing the SQL in question.... In other words, YMMV. Shalom, -- John Kanagaraj <>< http://www.linkedin.com/in/johnkanagaraj http://jkanagaraj.wordpress.com (Sorry - not an Oracle blog!) ** The opinions and facts contained in this message are entirely mine and do not reflect those of my employer or customers ** -- //www.freelists.org/webpage/oracle-l