To turn on trace for a specific event. exec dbms_system.set_ev(<SID>, <serial#>, <event>, 8, ''); Example: Enable trace at level 8 for session id 10046 exec dbms_system.set_ev(12345, 543211, 10046, 8, ''); -- To turn off the tracing: exec dbms_system.set_ev(<SID>, <serial#>, <event>, 0, ''); Example: exec dbms_system.set_ev( 1234, 56789, 10046, 0, '');