Defining the IMS catalog master database and partitions

The IMS catalog is a HALDB (high availability large database) database that is a partitioned, IMS full-function database type (ACCESS=PHIDAM,OSAM) with OSAM utilizing Physical Sequential data sets or VSAM Linear Data Sets. Prior to loading records into an IMS catalog, you must define the partitions to IMS.

The HALDB partition definitions for the IMS catalog are typically registered in the RECON data set by DBRC. DBRC provides support for database recovery, data sharing, automatically generating JCL control statements, log and data set management, and other database tasks.

However, the IMS catalog is not required to register with DBRC. You can define the IMS catalog database partitions with the IMS catalog partition definition utility (DFS3UCD0) instead of using DBRC. The DFS3UCD0 utility stores the catalog partition information in the catalog partition definition data set. This option is not available for other HALDBs.

When the IMS catalog partition definition data set is used, the IMS catalog is not registered with DBRC. The database protection support provided by DBRC, including backup and recovery support, is unavailable to the IMS catalog when a IMS catalog partition definition data set is used. Some HALDB utilities are supported with restrictions for an unregistered IMS catalog database.

Additionally, the IMS catalog database does not support a HALDB Partition Selection exit routine in any configuration. The IMS catalog database always uses the high-key partition selection method.

Choose one of the following options.