RDE maintenance at DBD or RECON change

Except for cases where RDEs are created automatically during initial database load or database reorganization, whenever you change a DBD, re-create the RDE by using the INIT.DB command of the LICON utility to reflect the updated DBD information.

If the IMS management of ACBs is enabled, re-create the RDE by specifying the IMS directory after the IMPORT DEFN SOURCE(CATALOG) command is issued.

There might be cases where you want to roll back a DBD change and use the DBD that was used before the change. If you restore the DBD that was used before the change, Integrity Checker must refer to the DMB information that reflects the DBD before the change as the correct DMB information. For such cases, except for cases where RDEs are restored automatically during database recovery, restore the expired RDE manually by using the RECOVER.DB command of the LICON utility.

To restore the RDE, both of the following requirements must be satisfied:

• Global option module specifies that historical copies of RDEs are kept (GENMAX=1 or higher).
• The RDE that was used before the DBD change is stored in the LICON data set as an expired RDE.

If the expired RDE does not exist, you must use the INIT.DB command of the LICON utility to manually create an RDE that contains the DMB information that was used before the DBD change.