Oracle dba: useful queries 2011-11-14

1. How do you know the database name from normal user(connected) in the database
2. How to find the user objects created by him/her in his/her schema
3. showing the table structure
4. sql which show you the allocated, Free and Used space in each of the datafiles
5. Monitor long running operations using v$session_longops
6. query can be used to monitor RMAN backup status
7. how to find a session with high archive logs
8. Query to find backupset sizes