Some useful session views - short description

V$SESSION --> displays information about the current session

V$SESSION_EVENT --> shows all the wait events waited for by the session. Note that it will show the data only if the session is still active in the database

V$SESSTAT --> shows the resource usage for a session
Some useful statistics visible in the V$SESSTAT view:
- physical reads: the number of database blocks retrieved from disk
- db block changes: the number of database blocks changed in the session
- bytes sent via SQL*Net to client: the bytes received from the client over the network, which is used to determine the data traffic from the client

V$ACTIVE_SESSION_HISTORY --> shows historical session information

DBA_HIST_ACTIVE_SESS_HISTORY --> contains the same data as V$ACTIVE_SESSION_HISTORY, but with less granularity, only every 10th second sampling