Hi, Can someone explain me, why does AT cause deadlocks. Eg: I updated a table x in session 1 and want to update same from session 2 but with AT. It goes into deadlock. But normal update works fine. I am not quite understanding the locking mechanism. Gone through docs, but not clear, or unable to understand. Can some one help please? Thanks Sent on my BlackBerry®-- //www.freelists.org/webpage/oracle-l