Explanation:
The backup of database files created using O/S commands must be manually restored and recovered. You can, however, register these files with the repository by using RMAN’s CATALOG command. The restore and recover operations hereafter would be possible using RMAN.
Reference:
Oracle 9i Net Services Administrator’s Guide
Oracle 9i Net Services Reference Guide
Oracle 9i Recovery Manager Reference
Oracle 9i Backup and Recovery Concepts

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