ABCs of z/OS System Programming Volume 3 - IBM Redbooks

6.18 Splitting a catalog
UCAT1
Figure 6-31 Splitting a catalog
REPRO MERGECAT
UCAT2
UCAT3
Splitting catalogs
You can split a catalog to create two catalogs or to move a group of catalog entries if you
determine that a catalog is either unacceptably large or that it contains too many entries for
critical data sets.
If the catalog is unacceptably large (that is, a catalog failure leaving too many entries
inaccessible), then you can split the catalog into two catalogs. If the catalog is of an
acceptable size but contains entries for too many critical data sets, then you can simply move
entries from one catalog to another.
To split a catalog or move a group of entries, use the access method services REPRO MERGECAT
command. Use the following steps to split a catalog or to move a group of entries:
1. Use ALTER LOCK to lock the catalog. If you are moving entries to an existing catalog, lock it
as well.
2. If you are splitting a catalog, define a new catalog with DEFINE USERCATALOG LOCK (see also
“Defining a catalog and its aliases” on page 339).
3. Use LISTCAT to obtain a listing of the catalog aliases you are moving to the new catalog.
Use the OUTFILE parameter to define a data set to contain the output listing (see also
“Merging catalogs” on page 361).
4. Use EXAMINE and DIAGNOSE to ensure that the catalogs are error-free. Fix any errors
indicated (see also “Checking the integrity on an ICF structure” on page 357).
Chapter 6. Catalogs 363