If you import the entire export dump file
from a full export, then all the database objects, including tablespaces, datafiles, and users, will
be created during the import. However, it is often useful to precreate tablespaces and users in
order to specify the physical distribution of objects in the database.
If you are only going to import part of the data from the export dump file, the tablespaces,
datafiles, and users that will own and store that data should be set up prior to the import.
Physical Backups
Physical backups involve copying the files that constitute the database. These backups are also
referred to as file system backups because they involve using operating system file backup
commands. Oracle supports two different types of physical file backups: offline backups and the
online backups (also known as cold and hot backups, respectively). You can use the RMAN utility
(see Chapter 12) to perform all physical backups. You may optionally choose to write your own
scripts to perform physical backups, but doing so will prevent you from obtaining many of the
benefits of the RMAN approach.
Offline Backups
Consistent offline backups occur when the database has been shut down normally (that is, not
due to instance failure) using the normal, immediate, or transactional option of the shutdown
command. While the database is ???offline,??? the following files should be backed up:
All datafiles
All controlfiles
All archived redo log files
The init.
Pages:
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613