
ISAM Datasets
7-28 User Reference
Connectivity Systems, Inc.—Copyright © 2006
Use Pursuant to Company Instructions
For Start Track 1, the SYS number for the overflow extent must be
different from the SYS number for the index and prime data areas, as
shown in the following example:
// DLBL MASTER,'EPIC.ISAM.MASTER.FILE',,ISE
// EXTENT SYSO4O,POOL80,4,1,1,15 Index
// EXTENT SYS041,POOL80,1,2,1,90 Prime
// EXTENT SYSO42,POOL80,2,3,1,30 Overflow
For each DD statements, specify DCB=DSORG=IS or
DCB=DSORG=ISU.
The three areas of an ISAM dataset, prime, index, and overflow, are all
defined as part of the same DD statement. However, the overflow area
must be defined using its own parameters, for example DSN, DCB, DISP,
SPACE, and VOL. You can define the prime and index areas
independently or together using one set of parameters.
Examples The following example shows each area with its own set of parameters.
Space and other information about the area follow the DSN parameter
identifying the area. Because the index area space is defined separately,
the space is defined with the primary-qty subparameter, SPACE=(TRK,1)
and not the index-qty, SPACE=(TRK(,,1)).
* //DATA DD DSN=CUSTOMER.MASTER(PRIME),
* // DISP=(NEW,KEEP)
* // UNIT=DISK
* // DCB=DSORG=IS,
* // SPACE=(TRK,45)
* // VOL=SER=POOL01
* // DD DSN=CUSTOMER.MASTER(INDEX),
* // DISP=(NEW,KEEP)
* // UNIT=DISK,
* // DCB=DSORG=IS,
* // SPACE=(TRK,1)
* // VOL=SER=POOL01
* // DD DSN=CUSTOMER.MASTER(OVFLOW),
* // DISP=(NEW,KEEP)
* // UNIT=DISK,
* // DCB=DSORG=IS,
* // SPACE=(TRK,15)
* // VOL=SER=POOL01
The following example shows one set of parameters used to define both
the prime area and the index area. In this case, SPACE is defined for the
index area by using the index-qty subparameter.
* //DATA DD DSN=CUSTOMER.MASTER,
* // DISP=(NEW,KEEP),
* // UNIT=DISK,
* // DCB=DSORG=IS,
* // SPACE=(TRK,(45,,1)),
* // VOL=SER=POOL01
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