Micro Focus Enterprise Developer 2.3 for Visual Studio 2015 > Programming > Mainframe Programming > JCL Support > Utility Programs > Emulations of Mainframe Utilities > VSAM Access Method Services (MFJAMS) > Commands > DEFINE CLUSTER

DEFINE CLUSTER

The DEFINE CLUSTER command creates a new VSAM data set. It creates the data and index files on the local machine and catalogs the data set name.

Parameters:

MFJAMS uses these parameters. All other parameters are ignored.

NAME(data-set-name): Name of the VSAM data set. This parameter is required.
INDEXED: Indicates a KSDS data set is being defined.
NONINDEXED: Indicates an ESDS data set is being defined.
NUMBERED: Indicates an RRDS data set is being defined.
KEYS(length offset): Length and offset, relative to 0, of the primary key field for a KSDS data set. The offset must be within the first 4096 bytes of the record. length plus offset must not exceed the maximum length of the record. The default is KEYS(64 0).
RECORDSIZE(average maximum): Average and maximum lengths of the records, expressed in decimal format. The default is RECORDSIZE(4089 4089).
MODEL(data-set-name): Name of a cataloged VSAM data set that has the same KEYS and RECORDSIZE parameters as this new data set. It is an alternative to specifying the parameters explicitly.
SHAREOPTIONS(crossregion[ crosssystem]): Defines component or cluster sharing among users. To ensure integrity, you should be sure that share options specified at the DATA and INDEX levels are the same. See the SHAREOPTIONS help topic for details.
Note: SMS-managed volumes and catalogs with SMS-managed data sets must not be shared with non-SMS systems.

The values of the SHAREOPTIONS parameters is assumed to be (3,3) when the data set is accessed in VSAM RLS or DFSMStvs mode.

Comments:

The file will be created as Variable Length records. This could be changed by the program that first writes to the file. If the first program accesses the file with fixed length records, then the file record type will be changed from variable to fixed.
INDEXED, NONINDEXED and NUMBERED are mutually exclusive. INDEXED is the default.
MFJAMS does not allow duplicate entries of the primary key.
KEYS and RECORDSIZE override the values obtained from MODEL.
MFJAMS does not support the Micro Focus split-key and key-compression features.

Example:

Here is a typical job to define a cluster:

//DEFCLUS  JOB  CLASS=A
//IDCSTEP  EXEC PGM=IDCAMS
//SYSPRINT DD   SYSOUT=*
//SYSIN    DD   *
DEFINE CLUSTER(NAME(TEST.KSDS.DUMMY) KEYS(5,0) -
       RECORDSIZE(80,80))

Note the use of the continuation character (-) in the DEFINE CLUSTER statement.