Use CATALOG in a restore operation only to selectively restore one or some databases or tables. To restore the majority of a tape or an entire tape, do not use CATALOG.
The UEN is saved in an archive header. Therefore, ARCMAIN knows which CATALOG table in the CATALOG database to access to retrieve catalog information for a restore operation. When ARCMAIN is about to search for the database header, it retrieves the CATALOG row for the database and uses its repositioning information for direct tape repositioning.
These operations occur if CATALOG was enabled for the archive operation:
- If CATALOG was enabled at the table level, ARCMAIN queries the CATALOG table for that specific table and uses the repositioning information for the table header search.
- If CATALOG was enabled at the object level at the time of the archive operation, then only database level repositioning is done using the catalog information; the tapes are scanned thereafter.