How COMPARE Works

The following table explains how COMPARE works:

Stage	Action
1	COMPARE uses the same logic paths as RESTORE to deblock and address a record as if it were to be restored.
2	A VSAM sequential GET macro is issued against the cluster, and the disk and backup records are compared.
3	Tests are made to verify the following: Equal length Equal content Equal RRDS slot numbers Same end-of-file points
4	Any discrepancies are reported by message GV906. For more information, see the CA FAVER Message Reference Guide.

Usage Rules

The COMPARE command has the following usage rules:

During comparison, the RESTORE parameters REUSE, *AMS, and UEXIT are edited, but they have no effect on processing.
Any of the RESTORE methods (CATALOG, CLUSTER, MCTLIST, and VOLUME) can be used. DD statements must be supplied for only those clusters that have the REUSE DDNAME=ddname parameter on the cluster name statement.
When clusters are opened, the catalog search order is as follows:
- STEPCAT
- JOBCAT
- Qualified data set name
- Master catalog

Samples

The following are sample COMPARE jobs:

Job	Explanation
COMPARE CATALOG EXCLUDE CL=TEST.+	Reads all clusters in the catalog except those that begin with TEST. and compares each record byte for byte.
COMPARE CLUSTER CL=CICS+	Reads all clusters that begin with CICS and compares each record byte for byte.