Batch Functions › Define and Initialize Data Sets › Define Data Sets

Define Data Sets

Use JCL similar to the following example to define a data set.

//DEFINEIT	EXEC	PGM=IDCAMS
//SYSPRINT	DD	SYSOUT=A
//SYSIN		DD	*
	DEFINE	CLUSTER ( -
		NONINDEXED			/* REQUIRED */ -
		SHAREOPTIONS(2 3)		/* OR (3 3) */ -
		SPEED -
		UNIQUE -
		CYLINDERS(5 5) -
		VOLUMES(VSAM01) -
		NAME('VTAM.TCADS') -
		RECORDSIZE(16377 16377)	/* MUST BE CISIZE-7 */ -
		CONTROLINTERVALSIZE( 16384) ) 

• The first parameter is required.
• The space allocation must be large enough for at least 11 control intervals.
• The control interval size must be a multiple of 4096 up to a maximum size of 28,672. The recommended size is 16,384.
• The record size must be 7 less than the control interval size.
• The other parameters have no special requirements.

Note: Use SHAREOPTIONS (2 3) if the data set is only being used in one region. Use SHAREOPTIONS (3 3) if the data set will be updated from two regions.