This piece of code show the list of events, set in the Oracle database

SET serveroutput ON  DECLARE   event_level NUMBER;  BEGIN   dbms_output.enable(20000) ;   FOR i IN 10000..33999 LOOP      sys.dbms_system.read_ev(i,event_level);      IF (event_level > 0) THEN         dbms_output.put_line(’Event ‘||TO_CHAR(i)||’ set at level ‘||                              TO_CHAR(event_level));
     END IF;
  END LOOP;
END;