RMAN

Oracle Incremental Backup Level 0 or 1

A level 1 incremental backup can be either of the following types:

  • differential backup, which backs up all blocks changed after the most recent incremental backup at level 1 or 0
  • cumulative backup, which backs up all blocks changed after the most recent incremental backup at level 0

Incremental backups are differential by default.

Incremental Backup full, 0 or  1 :

Backup level Advantage Disadvantage
Full backup Recovery requires just one single read form the backup storage device.No dependency between the two full backup. If one is lost you may use another recent full backup to recover certain amount of data, not everything. The type of backup cause longest type of outage during the backup time.It is the most expensive type of backup because it takes maximum amount of storage space among all types of backup.It also takes  much longer time to run than its other counterparts.
incremental Less media storage is required since it back up only the files that changed since the last backup.It take much less time in comparison to other types of backup. Recover requires a full backup and all the incremental backup.A complete data recovery depends on the all the incremental backups and the last full backup.
differential since differential backup takes backup of a series of changes since the last full backup, it requires less of number of backup sets to restore.They provide efficient recovery when full backup is taken rarely( e.g. monthly)  The amount of storage required for a differential backup may exceed than that is required for incremental backup when significant amount of data changes regularly.

Incremental_backup

Incremental_backup._1JPG

The following commands performs a level 0 backup of the database:

RMAN> BACKUP INCREMENTAL LEVEL=0 DATABASE;
RMAN> BACKUP INCREMENTAL LEVEL 0 DATABASE PLUS ARCHIVELOG;

 

The following commands performs a level 1 backup of the database:

RMAN> BACKUP INCREMENTAL LEVEL=1 DATABASE;
RMAN> BACKUP INCREMENTAL LEVEL 1 DATABASE PLUS ARCHIVELOG;
br: erman.
Advertisements
Standard

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s