Changing DEDB root addressable space with a two-stage randomizing routine using online change

You can change the DEDB root addressable space with a two-stage randomizing routine by using online change.

The UOW structure and root addressable allocation is specific to each area within each DEDB. However, a change to the number of root addressable CIs within one area can affect the number of root anchor points within the whole DEDB. If the DEDB uses a standard randomizing routine that randomly distributes database records across the entire database, changes to the root addressable allocation are database-level changes and procedurally must be handled as such. This topic is not applicable to such changes.

If, however, a two-stage randomizing routine is used for the DEDB, a change to an individual area UOW root addressable definition is an area-level change. A two-stage randomizing routine does not attempt to evenly distribute database records across all areas based on the total number of root anchor points in the entire DEDB. A two-stage randomizing routine is designated in the DBDGEN by coding the randomizing routine name as follows:

               RMNAME=(mmmmmmmm,2)

In prior releases of IMS, customers would get the following error message if a DEDB DBD had more than one operand in the RMNAME parameter:

       8, DBD130 - RMNAME OPERAND IS OMITTED OR INVALID

The same message will appear for this release of IMS if anything but 2 or 1 is specified as the second operand of RMNAME. (In this case, 2 should be specified.) Customers can still specify RMNAME=(mmmmmmmm) for standard randomizing routines.