Focal Point
Accessing MVS ISAM file with multiple record types

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June 09, 2004, 09:10 PM
<Mark Smith>
Accessing MVS ISAM file with multiple record types
I'm trying to create a webfocus reporting object for a file that contains multiple record type/formats.

For example:
Record1 - 01xxxxrrrrrrrrryyyyyyyyyyyyyyyyy
record2 - 02yyyyyyyxxxxrrrrrrr
record3 - 01xxxxrrrrrrrrryyyyyyyyyyyyyyyyy

In the above example the first two characters are the identifier of the record type, the x, r, y is data. For each record type, the data will be in the same format.

Is there a way to access this kind of file using one master file description?

Also, how would the master and access files be defined to read this kind of ISAM file?
June 14, 2004, 03:50 PM
<monte2000>
Hi there, Mark.

I spoke to the Product Manager and he said:

We haven't seen anybody using ISAM files, now every file is a VSAM file. Try the following:
Have a DUMMY root segment,
SEGNAME=DUMMY
FIELD =, A1,A1,$
SEGNAME=R1,PARENT=DUMMY,$
FIELD =RECTYPE,01,A2,A2,$
SEGNAME=R2,PARENT=DUMMY,$
FIELD= RECTYPE,02,A2,A2,$
SEG............
FIELD..........

There are good VSAM people in our Tech Support group, they might even have samples.

Hope this helps,

Monica
June 15, 2004, 08:14 PM
Chris Boylan
quote:
Originally posted by monte2000:
[qb]We haven't seen anybody using ISAM files, now every file is a VSAM file.[/qb]
ISAM files are not supported by IBM any longer, but some people do still use them. SUFFIX=ISAM in a MFD should still work (it invokes an earlier version of the FOCSAM interface that supports ISAM files).

The syntax for SUFFIX=ISAM is similar to SUFFIX=VSAM though you don't get the latest and greatest features of the VSAM interface. The code example above of unrelated RECTYPEs with a DUMMY parent segment should work just fine for either ISAM or VSAM files.

ISAM and VSAM files do not require an access file, just a master file description.

Hope that helps.

-Chris