i would definitely start from Here http://luhartma.blogspot.com/2006/05/active-session-history-in-oracle.html Fuad ----- Original Message ---- From: Laimutis Nedzinskas <Laimutis.Nedzinskas@xxxxxxxxxxxxx> To: oracle-l@xxxxxxxxxxxxx Sent: Thursday, April 26, 2007 1:09:27 PM Subject: Active Session History Anyone has information about Active Session History views (both V$ and DBA) So far I have more questions than answers how those views can be used... I am especially interested in the wait events columns like EVENTS_ID, TIME_WAITED, WAIT_TIME. What is funny enough is that EVENT_ID column is often just null in v$ view. Thank you in advance, Laimis N Fyrirvari/Disclaimer http://www.landsbanki.is/disclaimer -- //www.freelists.org/webpage/oracle-l