CATALOG Operations - TARA/ABU

CATALOG Operations

Archive

CATALOG no longer creates a table for each ARCHIVE statement; instead, CATALOG uses a single table named CATALOG. Multiple catalog tables are only created if the OLDCATALOG parameter is specified.

Restore

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.

Copy

Use CATALOG in a copy operation only to selectively copy one or some databases or tables. If most or all of a tape is being copied, do not use CATALOG.

Copy operations to the same system from which data was archived work similarly to restore operations with respect to the use of catalog information. To use CATALOG in a copy operation to a different system, knowing the UEN of the tape is necessary. Obtain the UEN by using an ANALYZE statement or by reading the output from an ARCHIVE statement. Use the UEN to archive and copy the corresponding CATALOG table from the source system to the target system before running a copy operation.

Mirrored Files

When two different data sets are archived by specifying File twice in an ARCHIVE statement, repositioning information is only saved in the CATALOG table for the primary, not the second (called the mirrored) data set.

If the mirrored data set is used in a restore operation with CATALOG, Teradata ARC detects that the mirrored data set is being used and automatically disables CATALOG.

Analyze

A CATALOG table can be generated offline using an ANALYZE statement that contains the CATALOG keyword, however, the ANALYZE statement does not recognize CATALOG specified as a runtime parameter. Tapes are scanned and the CATALOG rows are inserted into the CATALOG table for the database header records and the table header records in the tape set. After the CATALOG table is generated, it can be used in restore/copy operations.

Specifying CATALOG as a keyword in an ANALYZE statement is useful when a subset of objects must be restored or copied from a recataloged table set multiple times. However, for one-time operations, use a RESTORE or COPY statement without specifying CATALOG as a runtime parameter; catalog generation using an ANALYZE statement requires scanning the entire tape set anyway.

CATALOGFILE

Use the CATALOGFILE parameter to change the file name for the catalog with the CATALOGFILENAME command-line option. Disable CATALOGFILE by specifying NOCATALOGFILE or NOCTLGFILE. The effect is the same as NOCATALOG. Catalog information is not created during ARCHIVE, and is not used during RESTORE or COPY.

When using the CATALOG option of ANALYZE along with the CATALOGFILE / CATALOGFILENAME parameters, ANALYZE writes to both the CATALOG table on the database and the specified client-side file.

Note: In mainframe platforms (for example, z/OS), limit file names to eight characters.

NOCATALOG

NOCATALOG or NOCTLG disables CATALOG. No CATALOG table is created during an archive operation; no catalog information is used during a restore/copy operation.