SELECT a.sid parent_sid,
       a.logon_time,
       a.program,
       a.osuser,
       a.username,
       a.sql_id,
       ps.req_degree,
       ps.got_degree
  FROM (SELECT s.sid,
               s.osuser,
               s.USERNAME,
               s.status,
               s.sql_id,
               s.logon_time,
               s.last_call_et,
               UPPER(s.program) program
          FROM v$session s
         WHERE ((s.username IS NOT NULL) AND (NVL(s.osuser, 'x') <> 'SYSTEM') AND
               (s.TYPE <> 'BACKGROUND'))) a
  JOIN (SELECT DISTINCT qcsid,
                        CASE
                            WHEN req_degree > degree THEN
                             1
                            ELSE
                             0
                        END is_downgrade,
                        MAX(req_degree) req_degree,
                        MAX(degree) got_degree
          FROM v$px_session
         GROUP BY qcsid,
                  CASE
                      WHEN req_degree > degree THEN
                       1
                      ELSE
                       0
                  END) ps ON a.sid = ps.qcsid
 WHERE ps.is_downgrade = 1

כדי לאתר את השליפות שלא קיבלו פרוססים בכלל (ובעצם עשו downgrade to serial) ניתן להשתמש בשליפה הבאה:

SELECT sess.sid parent_sid,
		 logon_time,
		 sess.program,
		 sess.osuser,
		 sess.username,
		 sql_id,
		 TRUNC (last_call_et / 60) dur_minutes
  FROM v$sesstat sesstat, v$sysstat sysstat, v$session sess
 WHERE	  sesstat.statistic# = sysstat.statistic#
		 AND sesstat.sid = sess.sid
		 AND name = 'Parallel operations downgraded to serial'
		 AND sesstat.VALUE > 0
		 AND sess.status = 'ACTIVE'