Reading ESDS file randomly in Cobol Batch program

abdul · Posted: Tue Nov 18, 2003 7:48 am

Hi,
Is there anyway to read ESDS file randomly in Cobol Batch program.Can we read it using RBA? If yes how? and if you can provide me any reference program that will be appreciated.

Thanks
Abdul

mdtendulkar · Active User Joined: 29 Jul 2003 Posts: 237 Location: USA

Hello abdul,

there are 2 secnarios for this question.

1) The file is not sorted.
In this case you can not read the ESDS file randomly

2) The file is sorted on some key.
I think you can read the file randomly by using START command.
With the help of START command, you can point to the specific record using a key and then read sequentially.
Hope this helps.

Regards

Mayuresh Tendulkar[/u]

Johore · Specialist Joined: 12 Sep 2003 Posts: 19

Hi ,

Entry-sequenced data sets are accessed by address, either sequentially or directly.When addressed sequential processing is used to process records in ascending relative byte address (RBA) sequence, VSAM automatically retrieves records in stored sequence.
To access a record directly from an entry-sequenced data set, you must supply the RBA for the record as a search argument.
Skip-sequential processing is not supported for entry-sequenced data sets.

Skip- Sequential is use of START to locate a key and then reading sequentilally.

Hope this helps
johore

yashu_mys · New User Joined: 09 Nov 2003 Posts: 4 Location: India

Hi ,
For RBA i think one needs PL/1 , cobol doesn't support RBA right..?
Thanks ,
Yashvanth .

bluebird · Active User Joined: 03 Feb 2004 Posts: 127

on your question :
did u check in IBM manuals ?

xzsymr · New User Joined: 06 Jun 2003 Posts: 7 Location: NZ

Yes it is possible to read a ESDS randomly, You can define an alternate index, just like in a KSDS and use that as the path etc to access the file randomly

Ananya · New User Joined: 26 Feb 2004 Posts: 19 Location: Chennai

Dear Tendulkar,

Can START verb be used in ESDS?? are you sure about this? I don't think this is possible... but anyways,if I'm wrong pls correct me

Cheers
-Ananya

sai_dd · New User Joined: 01 Aug 2005 Posts: 5 Location: Cyprus

We can use START verb for accessing an ESDS file in a normal COBOL program too.

COBOL Syntax:

START <COBOL File name> ...

Sai

kiran.v2 · New User Joined: 29 Jul 2005 Posts: 9

hi
in this case we can use search verb for accessing the sequential file randomly