A database restore might be necessary when the data area or the log area is damaged, to recover from a logical error, or to copy the database.
Oracle restores consist of the following main categories:
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Full database restore: This is an in-place or out-of-place restore of all database files, the control file, and the server parameter file.
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Database subset: This is a combination of a restore of any of the following files:
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Archive logs
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Oracle control file
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Database archived redo logs
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Database clones: Create a clone so that you can:
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Duplicate large databases in a short amount of time
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Create test environments
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Retrieve data quickly without intensive resource use on the production environment
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Alleviate the load on production servers
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Note
If you are using Oracle Standard Edition database, set the number of restore streams (number of channels specified in the RMAN script) to 1. By default, the Commvault software sets the number of restore streams to 2. Because Oracle Standard Edition only supports one stream, the restore will fail if the number of restore streams is set to 2 or more.
PDB Restore Types
| Restore Type | When to Use | Result | Requirements and Notes |
|---|---|---|---|
| PDB clone (out-of-place restore) | Create a copy of a PDB under a new name or at a new location, while retaining the original. Use this option for testing, validation, reporting, or data extraction. | Creates a new PDB in an existing CDB; the original PDB remains unchanged. | Requires an existing target CDB and a new PDB name. A target database connection or recovery catalog is recommended. For cross-machine auxiliary restores, see the note below. |
| PDB point-in-time restore (PITR) | Recover an existing PDB to an earlier point in time, for example, after logical corruption, accidental data deletion, or an application issue. | Restores the PDB to the selected recovery point. | Requires backups and archived redo logs that cover the desired recovery time. This is an in-place restore. |
| Duplicate PDB restore | Restore a PDB when no CDB is available at the destination. | Creates a restored copy of the selected PDB in the destination CDB. | Requires the source PDB backup data, a destination CDB or recovery catalog as applicable to the restore workflow, and sufficient destination storage and resources. |
Note
For a cross-machine PDB clone that uses an auxiliary restore, enable bUseDuplicateForAuxiliary.
Control CPU Usage
To control CPU usage for restores, see control CPU usage for database restores.
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