1) To find out lock for big long running sql during upgrade
SELECT s1.username || '@' || s1.machine || ' ( SID=' || s1.sid || ' )
is blocking ' || s2.username || '@' || s2.machine || ' ( SID=' || s2.sid || ' ) ' AS blocking_status FROM v$lock l1,
v$session s1, v$lock l2, v$session s2
WHERE s1.sid=l1.sid AND s2.sid=l2.sid
AND l1.BLOCK=1 AND l2.request > 0 AND l1.id1 = l2.id1 AND l1.id2 = l2.id2;
