Oracle lock이 걸렸을 때 blocker 찾기

SELECT/*+ ordered use_hash( sw l ) */
  s.sid
 ,s.serial#
 ,s.module
 ,s.program
 ,sw.seconds_in_wait Sec
 ,TO_CHAR(l.sid) ||','||TO_CHAR(s1.Serial#)|| ':' || sw1.event ||decode(sw1.seconds_in_wait,0,NULL,'('||sw1.seconds_in_wait||'secs)')  holder
 FROM  

        v$session_wait sw
,       v$session      s
,       v$lock         l
,       v$session s1
,       v$session_wait sw1
WHERE  sw.event like 'enq%'
AND    S.sid    = sw.sid
AND    l.id1(+) = sw.p2
AND    l.id2(+) = sw.p3
AND    l.lmode(+) > 0
AND    l.sid(+) <> sw.sid
AND    s1.sid=sw1.sid
AND    l.sid=s1.sid
ORDER BYl.sid, sw.seconds_in_wait DESC;