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deepa12 Beginner
Joined: 05 Apr 2005 Posts: 131 Topics: 64 Location: chennai
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Posted: Tue Jul 03, 2007 6:50 am Post subject: cics - alternate index |
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I have a VSAM KSDS with below key
dc
warehouse
assignment no:
cubic sz
location
All the pgms are acecssing the file in this order and it means a lot
But in 1 pgm alone the no: of generic reads can be reduced if we access the file as below
dc
warehouse
assignment no
location
cubic sz
i.e we interchange the cubic sz and location field.
We do not know how to accomplish this without disturbing the other pgms
And we cannot disturb the other pgms since there some logics based on the sequnce of cubic sz
1 choice i have is create an empty cluster with the required key sequence
Then do an internal SORT from CICS COBOL pgm & populate the o/p
Is this possbile. i.e using SD entry in CICS pgm
Is there anyother method in VSAM to create alternate index where the key is in 2 different palces i.e until assigment no: then location, location & this followed by cubic sz
ta
rgs
deepa _________________ deepa |
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kolusu Site Admin

Joined: 26 Nov 2002 Posts: 12378 Topics: 75 Location: San Jose
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Posted: Tue Jul 03, 2007 7:19 am Post subject: |
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Is there any other method in VSAM to create alternate index where the key is in 2 different palces i.e until assigment no: then location, location & this followed by cubic sz
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deepa12,
No. Your key fields must be sequential ie they must be clubbed together
Kolusu
PS: Please stop using Chat lingo _________________ Kolusu
www.linkedin.com/in/kolusu |
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dbzTHEdinosauer Supermod
Joined: 20 Oct 2006 Posts: 1411 Topics: 26 Location: germany
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Posted: Tue Jul 03, 2007 8:46 am Post subject: |
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deepa12 wrote: | 1 choice i have is create an empty cluster with the required key sequence
Then do an internal SORT from CICS COBOL pgm & populate the o/p
Is this possbile. i.e using SD entry in CICS pgm |
I don't believe IBM has removed the FD/SD constraints from CICS pgms.
anyway, unless you are building the keys for all the records in the VSAM files you are wasting your time. Why do think that numerous reads due to generic and unsorted aix is going to be slower than reading in a handful of records, sorting them and the writing them to a new ksds file so that you can do direct reads?
The 1 program that needs a 'new aix', how important is it to the business objective? How often is it invoked? These are the kind of things that need to be considered, not that this program spends a lot of time reading a poorly designed file- or maybe it was designed properly and this 1 program was poorly designed; or the resource cost is justified for this one program.
other factors for consideration:- when are inserts made -new records added?
- how many records are in the KSDS?
- how often is it reorged?
- are there future business requirements that may impact this quick&dirty fix?
- are there future business requirements that may mean expanding the present situation?
depending on the record size, ci-size, if there are enough CICS buffers assigned, the program may not be doing physical reads anyway. Trying to reduce the number of reads may actually increase the resource cost. _________________ Dick Brenholtz
American living in Varel, Germany |
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Earl Beginner
Joined: 09 Jun 2007 Posts: 26 Topics: 1
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Posted: Thu Jul 05, 2007 3:07 pm Post subject: |
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please explain a little more.
is the VSAM ksds CICS file ?
If so, is it updated by CICS applications ?  |
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deepa12 Beginner
Joined: 05 Apr 2005 Posts: 131 Topics: 64 Location: chennai
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Posted: Fri Jul 06, 2007 3:23 am Post subject: |
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Hi Thanks for this
The system is very old & complex am not too sure if i can delve into it that deeply Anyway i will look into these aspects
deepa _________________ deepa |
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