Commands that support dynamic resource definition

With dynamic resource definition (DRD), you can use type-1 and type-2 commands to define resource and descriptor definitions.

The following IMS type-2 commands support DRD.

CREATE DB
CREATE DBDESC
CREATE LTERM
CREATE MSLINK
CREATE MSNAME
CREATE MSPLINK
CREATE PGM
CREATE PGMDESC
CREATE RTC
CREATE RTCDESC
CREATE TRAN
CREATE TRANDESC
DELETE DB
DELETE DBDESC
DELETE DEFN (supported for the IMSRSC repository only)
DELETE LTERM
DELETE MSLINK
DELETE MSNAME
DELETE MSPLINK
DELETE PGM
DELETE PGMDESC
DELETE RTC
DELETE RTCDESC
DELETE TRAN
DELETE TRANDESC
EXPORT DEFN
IMPORT DEFN
QUERY DB
QUERY DBDESC
QUERY MEMBER
QUERY PGM
QUERY PGMDESC
QUERY RTC
QUERY RTCDESC
QUERY TRAN
QUERY TRANDESC
UPDATE DB
UPDATE DBDESC
UPDATE MSLINK
UPDATE MSNAME
UPDATE MSPLINK
UPDATE PGM
UPDATE PGMDESC
UPDATE RTC
UPDATE RTCDESC
UPDATE TRAN
UPDATE TRANDESC

The following IMS type-1 commands support DRD:

/CHECKPOINT
If automatic export is enabled, and one or more resource or descriptor definitions have been created, updated, or deleted since the last checkpoint, the /CHECKPOINT command causes changed resource and descriptor definitions with a status of EXPORTNEEDED to be written to the system resource definition data set (RDDS) that contains the oldest data, the IMSRSC repository, or both.
/CHECKPOINT DUMPQ|FREEZE|PURGE
If automatic export is enabled, and one or more resource or descriptor definitions have been created, updated, or deleted since the last checkpoint, the /CHECKPOINT DUMPQ|FREEZE|PURGE command causes all resource and descriptor definitions to be written to the system RDDS that contains the oldest data, the IMSRSC repository, or both.
/MODIFY
If DRD is enabled and MODBLKS is specified on the /MODIFY command, the command fails.

The X'22' log record represents an action that is generated by a type-2 command. It is written for most type-2 commands that are recoverable and for some type-2 commands, such as QUEUE and UPDATE, for diagnostic information. Refer to DFSLOG22 for mapping of the X'22' log record. For most commands, the X'22' log records indicate that the type-2 command is recoverable, and it is used to reprocess the command during a warm or emergency restart. The X'22' log record is also used to communicate the command changes to the XRF alternate system, the DBCTL warm standby system, or the FDBR system. For some commands, the X'22' log records are for diagnostics only and are not used to recover or reprocess the command.

For the transaction, program, routing code, and database resources and descriptors, the X'22' log record tracks the changes made to the runtime resource and descriptor definitions that result from the CREATE, UPDATE, DELETE, and IMPORT commands, and the MODBLKS online change procedure.

For the MSC remote LTERM, logical link (MSLINK), physical link (MSPLINK), and logical link path (MSNAME) resources, the X'22' log record tracks the changes made to the runtime resource definitions that result from the CREATE, UPDATE, and DELETE commands

The EXPORT command does not generate a X'22' log record.

In addition to being able to dynamically create, update, query, and delete runtime resource and descriptor definitions, with DRD you have other benefits, including:

Type-2 command benefits, including the ability to sort, scroll, and use wildcards in the command.
Returned command completion code text is displayed with a brief description of the completion code.
All create, update, and delete activities are logged in the log record X'22', to aid in recovery after a warm or emergency restart.
Create, update, access time stamps are maintained.

If DRD is not enabled for MODBLKS resources, you can use the following type-2 commands:

QUERY DB
QUERY IMS
QUERY PGM
QUERY RTC
QUERY TRAN
UPDATE DB START()
UPDATE DB STOP()
UPDATE IMS
UPDATE PGM START()
UPDATE PGM STOP()
UPDATE RTC START()
UPDATE RTC STOP()
UPDATE TRAN SET(LOCK())
UPDATE TRAN START()
UPDATE TRAN STOP()

If DRD is not enabled for MSC resources, you can use the following type-2 commands:

QUERY LTERM
QUERY MSLINK
QUERY MSNAME
QUERY MSPLINK
UPDATE MSLINK
UPDATE MSNAME
UPDATE MSPLINK

The EXPORT command can be issued in a non-DRD enabled IMS system. However, in a non-DRD enabled IMS system, the only RDDS that can be exported to is a non-system RDDS.