HALDB alter and offline reorganization when IMS manages ACBs
If you perform the offline reorganization process to alter a HALDB database when IMS manages ACBs, the HD Reorganization Unload utility (DFSURGU0) and the HD Reorganization Reload utility (DFSURGL0) retrieve the active DBDs from the directory data set of the IMS catalog. You must also issue the IMPORT DEFN SOURCE(CATALOG) command.
Before you start the offline reorganization, access to the database must be stopped by issuing either the IMS type-2 command UPDATE DB NAME(partition_name) STOP(ACCESS) command or the IMS type-1 command /DBRECOVERY.
An offline reorganization is performed by unloading the database with the HD Reorganization Unload utility (DFSURGU0) and then reloading the database with the HD Reorganization Reload utility (DFSURGL0).
The HD Reorganization Unload utility automatically unloads the records from the active portions of both the A–J and M–V data sets.
The HD Reorganization Unload utility automatically retrieves the active database records from the directory data set of the IMS catalog. When you use the HD Reorganization Reload utility to reload the database with the changed definition, by default, the reload utility obtains the active database from the directory data set of the IMS catalog. The altered database is in the staging data set of the IMS catalog. You can specify the STAGING keyword on the DFSACBPD DD statement in the execution JCL to obtain the pending database from the staging data sets.
The IMS DD statement in the execution JCL of both the HD Reorganization Unload utility and the HD Reorganization Reload utility becomes optional and is ignored by the IMS system.
The HD Reorganization Reload utility loads all records into the A–J data sets. If the HALDB alter function was writing to the M–V data sets, the characteristics of the A–J data sets might not be correct. Before you reload the database, ensure that the A-J data sets are allocated enough storage for the altered segment sizes and, if you are altering VSAM data sets, that the VSAM CI sizes of the A–J data sets are correct.
After the database is reloaded, issue the IMS type-2 IMPORT DEFN SOURCE(CATALOG) command to enable the altered database in the online system and to reset the HALDB alter flags and counters in the RECON data set.
After you issue the IMS type-2 IMPORT DEFN SOURCE(CATALOG) command, you can restart the database.