VSAM ESDS- JCL for creating ESDS dataset:

VSAM Dataset Types VSAM KSDS


ESDS stores records in sequential order.

In ESDS Records can be accessed sequentially based on the order in RBA value.

In ESDS, Records can be accessed randomly by providing RBA value of the desired record.

In ESDS, each record is identifying by its relative byte address (RBA).

For example, An ESDS data set of 1000 byte records. The first record relative byte address is 0, similarly second one is 100, etc,.

ESDS records can be fixed length or variable length.

The records in an ESDS cluster are stored in the order in which they are entered into the dataset.

Records may not be deleted from an ESDS.

If any record inserted, then it will be appended to the dataset at the end.

If any record updated, then there will be no change in record positions.

ESDS dataset only contains data component and no index component.

ESDS dataset can maintain only position of the record.

ESDS can be used by IMS, DB2, z/OS and UNIX.


VSAM Dataset Types VSAM KSDS