SHUTDOWN THE DATABASE:
There are 4 ways to shutdown database
1- SHUTDOWN NORMAL:
- No new connection can be made
- Oracle server waits all users to disconnect
- database and redo buffer written to the disk
- Background process terminated and SGA remove from memory
- Oracle closes and dismount database before shutdown
- Next startup does not require recovery
2- SHUTDOWN TRANSACTIONAL:
- No new connection can be made
- User automatically disconnect after completing the transaction in progress
- When all transaction finished shutdown occur immediately
- Next startup does not require recovery
3- SHUTDOWM IMMEDIATE:
- Current SQL statement being processed is not completed
- Oracle server does not wait for the user who are currently connected to the database
- Oracle closes and dismount database before shutdown.
- Next startup does not require recovery
4- SHUTDOWN ABORT:
- Oracle does not wait for user currently connected to the database
- Database and redo buffers are not written to the disks
- The instance terminated without closing the files
- The database is not close or dismounts
- Next startup requires instance recovery.
