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Storage Checkpoints can be created by specifying one of the following options: online, offline, or instant. To create a Storage Checkpoint with the online option, the database should be online and you must enable ARCHIVELOG mode for the database. For the offline option, the database should be offline.
During the creation of the Storage Checkpoint, the tablespaces are placed in backup mode. Because it only takes a few seconds to take a Storage Checkpoint, the extra redo logs generated while the tablespaces are in online-backup mode are very small. You can roll back the entire database or individual tablespaces or datafiles to an online or offline Storage Checkpoint. After the rollback is complete, you may roll the database forward to restore the database if you have used an online Storage Checkpoint.
For the instant option, the database should be online and it can be running in either ARCHIVELOG or NOARCHIVELOG mode. You can only roll back the entire database to an instant Storage Checkpoint. Rolling back individual tablespaces or datafiles to an instant Storage Checkpoint is not possible. After the rollback is complete, you need to perform database recovery. Rolling the database forward is not supported; that is, you cannot apply archived redo logs.
To allow the easiest recovery, always keep ARCHIVELOG mode enabled, regardless of whether the database is online or offline when you create Storage Checkpoints.