A snapshot freezes the current state of the data area. When you create a snapshot, you can continue to work with the data as normal and later revert to the state of the data area when the snapshot was made.
A snapshot does not prevent system failures. To be able to restore your data after a system failure, you must carry out data and log backups at regular intervals.
The database instance is in the ADMIN operational state.
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1. You create a snapshot.
2. You continue to work with the data as normal.
3. You decide between the following two options:
¡ Revert to the snapshot (reject all the changes since the snapshot was made)
¡ Delete the snapshot (permanently accept all the changes since the snapshot was made)
See also:
Concepts of the Database System, Snapshots: Freezing the Data Area.