Oracle gives a few choices to taking reinforcements of a data set, including Level 0 and Level 1 gradual reinforcements. Oracle Level 0 and Level 1 incremental backup procedures are as follows:
1. Make a complete backup: You must first take a full backup of the database before you can take incremental backups. The foundation for subsequent incremental backups is this backup.
2. Take a Level 0 steady reinforcement: All of the database's data is backed up in a Level 0 incremental backup, which serves as a starting point for subsequent backups. To take a Level 0 reinforcement, utilize the Reinforcement Steady LEVEL 0 Data set order.
3. Make an incremental Level 1 backup: Regardless of whether it was a full or incremental backup, a Level 1 incremental backup stores all data that has changed since the previous backup. Use the BACKUP INCREMENTAL LEVEL 1 DATABASE command to create a Level 1 backup.
4. Integrate backups: The Level 0 backup and all subsequent Level 1 backups must be combined chronologically in order to restore the database. The database can be restored with the RESTORE DATABASE command.
It is essential to keep in mind that, in comparison to full backups, incremental backups may necessitate additional storage space and may take longer to restore. To make sure you can meet your recovery point and recovery time goals, it is recommended that you carefully plan and test your backup strategy.
Incremental backups can be either level 0 or level 1. A level 0 incremental backup, which is the base for subsequent incremental backups, copies all blocks containing data, backing the datafile up into a backup set just as a full backup would. The only difference between a level 0 incremental backup and a full backup is that a full backup is never included in an incremental strategy.
A level 1 incremental backup can be either of the following types:
A differential backup, which backs up all blocks changed after the most recent incremental backup at level 1 or 0.
RMAN> BACKUP INCREMENTAL LEVEL 1 DATABASE;
A cumulative backup, which backs up all blocks changed after the most recent incremental backup at level 0.
RMAN> BACKUP INCREMENTAL LEVEL 1 CUMULATIVE DATABASE; # blocks changed since level 0
