System Packages Oracle PLSQL

SQL> BEGIN
  2    DBMS_TRACE.SET_PLSQL_TRACE(
  3      DBMS_TRACE.TRACE_ALL_CALLS +
  4      DBMS_TRACE.TRACE_ALL_EXCEPTIONS);
  5  END;
  6  /
PL/SQL procedure successfully completed.
SQL>
SQL>
SQL>