Use the REGISTER DATABASE command to register the target database in the recovery catalog so that RMAN can maintain its metadata. RMAN obtains all information it needs to register the target database from the target database itself.


Execute this command only at the RMAN prompt. RMAN must be connected to a recovery catalog and a mounted or open target database. The database that you are registering must not be currently registered in the recovery catalog.

You can only register a target database with a DBID that is unique within the recovery catalog. Databases with the same name are permitted if the DBID values are different. The database that you are registering must not be a standby database.

Usage Notes

RMAN automatically registers a new standby database in the recovery catalog when the primary database for the standby database is registered in the recovery catalog and either of the following conditions is true:

  • RMAN is connected to a database instance that has a DB_UNIQUE_NAME unknown to the recovery catalog.

  • You execute the CONFIGURE DB_UNIQUE_NAME command for a database that is not known to the recovery catalog.

If you are using RMAN in a Data Guard environment, then the REGISTER DATABASE command can register a primary database or a physical standby to which RMAN is connected as TARGET.

In Oracle Database 19c, use the REGISTER DATABASE command to explicitly register a physical standby database to the recovery catalog. After registering the physical standby database, RMAN also performs a full resynchronization using the standby control file. The primary benefit of this feature is that you can avoid connecting to a primary database to perform a full resynchronization.


There are a few limitations for RMAN to perform a full resynchronization using the standby control file. See, Recovery Catalog Resynchronization in a Data Guard Environment in the Backup and Recovery User's Guide.

The REGISTER DATABASE command fails when RMAN detects duplicate DBIDs. This situation can arise when databases are created by copying files from an existing database rather than by using the DUPLICATE command. If this failure occurs, then you can change the DBID of the copied database with the DBNEWID utility and then retry the REGISTER DATABASE command.

If you open a database with the RESETLOGS option and later register this database in the recovery catalog, then the recovery catalog records the DB_NAME for the old incarnations as UNKNOWN because the old incarnations were not previously registered. Do not try to remove these records.


If you are using RMAN with different target databases that have the same database name and DBID, then be careful to always specify the correct recovery catalog schema when invoking RMAN.

See Also:

Oracle Database Utilities to learn how to use the DBNEWID utility


Example 3-14 Registering a Database

This example registers a new target database in the recovery catalog. Sample output is included.

connected to target database: PROD (DBID=1619241818)
recovery catalog database Password: password
connected to recovery catalog database

database registered in recovery catalog
starting full resync of recovery catalog
full resync complete