Before you can use the /GROUP command CDBM requires a file in which all your predefined commands can be stored. This file, DFHDBFK, is the CDBM GROUP command file. It is a VSAM KSDS.
The DFHDBFK file is not required until you first attempt to use the /GROUP command.
Sample JCL to enable you to define this file and optionally to place some of your group definitions within it is provided in the CICS® System Definition Guide. The example given there also shows you how to batch load this file if you want to do so.
You may load many definitions in this way, or load none. You may use whatever means you prefer to define this file and and to maintain its content. One method of maintainting the content once the file is defined is provided by CDBM which offers a Maintenance function for the DFHDBFK file.
To use the the /GROUP command functions of the CDBM transaction, add the data set name of the group command file to the definition of the DFHDBFK file within the DFHDBCTL group. For information about how to do this, see the CICS Resource Definition Guide.
Each record in the DFHDBFK file may be up to 1428 characters long, as follows:
field | length | content | description |
---|---|---|---|
1 | 12 | Group | a 12-character field containing your chosen name for this group. The acceptable characters are A-Z 0-9 $ @ and #. Leading or embedded blanks are not allowed, but trailing blanks are acceptable. |
2 | 10 | IMS Command | a 10-character field containing any of the IMS command
verbs that are valid for CDBM (see the CICS IMS™ Database Control Guide
for details). Leading or embedded blanks are not allowed, but trailing blanks
are acceptable.
Note:
The validity of the IMS command verb is not
checked by CDBM. Invalid values will be reported by IMS when the command is
attempted. |
3 | 1406 | IMS Command parameters | Up to 1406 characters of parameters appropriate to the
chosen IMS command verb. (This will often consist of lists of databases.)
Note:
Wildcard characters may not be used in the parameters stored in
the CDBM Group command file. This is unlike the other functions of the CDBM
transaction which permit the use of wildcard characters to describe multiple
similarly named databases. |
If you press the Maintenance key (PF2) on the main CDBM panel, you get the panel shown in Figure 22.
CDBM CICS/DBCTL COMMAND GROUP MAINTENANCE _ ACTION A add B browse D delete R read U update ____________ GROUP __________ IMS COMMAND > < > < > < > < > < > < > < > < > < > < > < > < > < > < > < > < > < > < > < F1=Help F3=Exit F12=Cancel
The input fields are:
Group, IMS Command and IMS Command parameters are described in the section Record layout in the CDBM GROUP command file
The Action field will accept one of the following:
Add a new record to the DFHDBFK file. If the key already exists, the Add fails.
Displays the contents of the command file, record by record. Specify any key (or none) to indicate where you want the browse to start. Each time you press ENTER, Browse moves on to the next record. At the end of the file you will be prompted to wrap around to the start of the file. You can accept this or not as you prefer. Incomplete keys, and unknown keys are also acceptable as start points. If no key is provided, the browse starts at the first record in the file.
If you have used Browse to locate a specific record for deletion or for update, remember to use Read before either Delete or Update.
Delete a record from the DFHDBFK file. A Delete must be immediately preceded by a Read to lock the required record.
Read displays a specific record. Unlike Browse it does not operate on partial, or absent keys, and does not present the next record when you press ENTER.
Read is required before those actions (Delete and Update) which change an existing record. It locks that record against the possibility of being changed by another operator. This action also serves to help you confirm that the correct record has been selected.
A lock is released by exiting the CDBM maintenance panel, or by your next CDBM Maintenance action (whether that is the Update or Delete you had contemplated, or something different entirely).
Update a record in the DFHDBFK file. An Update must be immediately preceded by a Read to lock the required record.
You cannot update the key fields (GROUP and IMS COMMAND).