
Multi-Dataset Processing
User Reference
Connectivity Systems, Inc.—Copyright © 2006
Use Pursuant to Company Instructions
7-15
Multi-Dataset Processing
Description This section explains the concept of multi-dataset groups and describes
their processing requirements and options.
A multi-dataset group consists of a prime dataset and up to 9,998
subdatasets. A multi-dataset group can reside on a single tape volume or
on multiple tape volumes. BIM-EPIC will automatically handle tape
positioning for both input and output processing.
!
WARNING:
All datasets participating in a multi-dataset group MUST conform
to a standard dataset format defined by the Logical Input Output
Control System (LIOCS).
The standard dataset format consists of three components for each
dataset:
Header label set, followed by a tape mark
Data, followed by a tape mark
Trailer label set, followed by at least one tape mark (the last
dataset on a volume will be followed by two tape marks.
Almost all programming languages and utility programs create datasets
which conform to this standard format.
!
WARNING:
Do not use the BIM-EPIC multi-dataset capability for VSE LIBR
and IDCAMS BACKUP commands.
The LIBR BACKUP command and the IDCAMS BACKUP command
create datasets which do not conform to the standard data format. They
insert additional tape marks in the output data, thereby making it
impossible for BIM-EPIC to properly position a volume to any
subsequent subdataset.
Prime Datasets The first dataset on the first reel of a multi-dataset group is called the
prime dataset. The prime dataset owns all the volumes in the group and
controls their physical attributes.
All datasets that follow the prime dataset in the group are called
subdatasets. When defined, these subdatasets must be associated with the
prime dataset. BIM-EPIC supports two methods of establishing this
association:
Automatically (using the DSN Catalog)
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