Backing Up Oracle - Computing at Cornell

An incremental backup can be performed on:
Individual data files
Tablespaces
The entire database
Incremental backup of control files or archived logs is not supported. There
are two types of incremental backups: non-cumulative and cumulative.
6.3.3.1 Non-cumulative incremental backup
A non-cumulative incremental backup backs up only those blocks that have
changed since the previous incremental backup at the same or lower level.
This is the default mode of operation for incremental backups.
A level 0 backup backs up all blocks that contain data. It performs the same
backup as a full backup. A level 0 backup is required for subsequent
incremental backups at other levels. An incremental backup at a level greater
than level 0 backs up only those blocks that have changed since a previous
incremental backup at the same or lower level. The size of the backup
depends on the number of blocks modified.
Figure 15 illustrates part of a monthly cycle of non-cumulative incremental
backups. The cycle is based on backup levels 0, 1, and 2. A weekly backup is
performed at level 0 on Sunday, incremental backups level 2 are performed
on Monday to Wednesday and on Friday and Saturday, and weekly
incremental backups at level 1 on each Thursday.
Figure 15. Non-cumulative incremental backups
Chapter 6. Oracle backup considerations on UNIX 79