When you delete a data set, the BCS, VVDS, and VTOC entries for the data set are removed. If you later recover a BCS, there might be BCS entries for data sets which have been deleted. In this case, the data sets do not exist, and there are no entries for them in the VVDS or VTOC. To clean up the BCS, delete the BCS entries.

For non-VSAM data sets and VSAM clusters, alternate indexes, and page spaces, the DELETE command with the NOSCRATCH option removes the BCS entries. If you define the appropriate RACF® FACILITY class, only authorized users are allowed to use NOSCRATCH on SMS-managed data sets.

When you use the NOSCRATCH option, the VVDS and VTOC are not changed. Using this option is the same as uncataloging a data set. After deleting the BCS entry, you can recatalog the data set.

The BCS record for a VVDS might only be deleted if there are no records in the VVDS for data sets cataloged in the BCS. When the BCS record for a VVDS is deleted, the back-pointer to the BCS in the VVDS is also deleted.

You might also need to delete VSAM truename records. VSAM data sets and objects which have more than one component have more than one BCS entry. For example, a key-sequenced data set has entries for the data component and the index component ("truename" records), as well as an entry for the data set itself ("sphere" record).

In order to use a VSAM data set or object, there must be a sphere record for it. If that record is missing, delete the truename records for the data set's components using DELETE TRUENAME. Then recatalog the data set with the DEFINE command. If the sphere record is accessible, then the sphere record and associated truename records can be deleted using the NOSCRATCH option of DELETE.

You can only delete a truename record if the associated sphere record is missing or inaccessible. This problem can be identified using the DIAGNOSE command. You cannot define a data set with the same name as a data set with a missing sphere record: the data set's name cannot be reused until the truename records are deleted.