Originally posted by Raminder
My second query is more basic. How can one have more than one user in the same schema? I mean when we create an Oracle user, his schema is automatically created with the same name. So why have two different columns (Scemaname and Username) in the V$Session view?
With appropriate privileges user can isue the following command: ALTER SESSION SET current_schema = [some_other_schema];

I'm not going into details why this might be usefull, but this is exactly the reason why there are two columns in V$SESSION.

If in the abowe example the connected user is SYSTEM and he isue:

ALTER SESSION SET current_schema = SCOTT;

then querying the V$SESSION for his session would return 'SYSTEM' as username and 'SCOTT' as schemaname.