v$session_wait and v$session_event

[jt]

I am having trouble understanding the difference between v$session_wait and v$session_event. I read the oracle reference documentation and still don't get it. Anybody can explain this to me? Thanks.

[pando]

session_wait shows what is each session waiting at at the instance you issue select * from v$session_wait

session_event would be the sum of session_wait in each session and each event

system_event would be the sum of all waits in session_event

normally I use session_wait to check for enqueue or those transactions that is taking long time (and see what they are doing/waiting)

I query session_event when I am tracing an user and see how many waits, wait time etc his session has been facing

HTH