The drop operation pursues the following process:
1 Sets an exclusive lock on the user.
2 Verifies that the user is empty.
If the user is not empty, then the DROP USER action aborts.
3 Verifies that the user does not own any other databases or users.
If the user owns any databases or users, then the DROP USER action aborts.
4 Drops the database.
5 Adds the PERM and TEMP space that the drop makes available to that of the immediate owner database or user.
After a user is dropped, it cannot be recovered by using the Dump and Restore utility unless it is restored.