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davinski.bby · Beginner Joined: 30 Jul 2007 Posts: 31 Topics: 10

i need to update certain certain records given a condition in a vsam file using JCL .

example:

Nic Clouston · Posted: Thu Oct 18, 2007 12:23 pm Post subject:

Not by JCL - you need a program - either written by yourself or more likely using whichever sort tool your shop uses. search on matching files in the utilities forum for a start.
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davinski.bby · Beginner Joined: 30 Jul 2007 Posts: 31 Topics: 10

What Sort Tool can i use? thanks.

vkphani · Intermediate Joined: 05 Sep 2003 Posts: 483 Topics: 48

davinski,

The below job gives you the desired results.

krisprems · Posted: Fri Oct 19, 2007 1:41 am Post subject:

vkphani
Always try to use OUTREC where ever possible, avoid using INREC. This improves the efficiency of Your SORT JCL.
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vkphani · Intermediate Joined: 05 Sep 2003 Posts: 483 Topics: 48

krisprems · Posted: Fri Oct 19, 2007 3:38 am Post subject:

vkphani
yes its true, but may not find the difference in performance untill and unless you process huge file's.
Note Some times by using INREC also you can improve the efficiency, consider a scenario like this:
In i/p file if you have data of LRECL=3000 and you require the o/p of LRECL=100 then in this scenario use INREC and reformat the records then perform SORT.
Since the flow of SORT would be like this:
1. INREC
2. SORT/SUM FIELDS
3. OUTREC
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krisprems · Posted: Fri Oct 19, 2007 3:42 am Post subject:

You can refer to this link for further details

INREC Statement Notes
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vkphani · Intermediate Joined: 05 Sep 2003 Posts: 483 Topics: 48

Thaks for the link kris.

Bill Dennis · Posted: Fri Oct 19, 2007 8:11 am Post subject:

When I read the link provided there is no mention of OUTREC being better performance than INREC. Only that it's more convenient using OUTREC because the SORT FIELD positions are the original record locations.

As kris admits, INREC is actually better for performance when you can reduce the record to only the meaningful fields.
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Disclaimer: My comments on this foorum are my own and do not represent the opinions or suggestions of any other person or business entity.

krisprems · Posted: Fri Oct 19, 2007 9:32 am Post subject:

Bill Dennis

Frank Yaeger · Posted: Fri Oct 19, 2007 10:36 am Post subject:

Actually, for a COPY, there is usually no difference in performance between INREC and OUTREC. For a SORT, there can sometimes be a difference in performance.
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Frank Yaeger - DFSORT Development Team (IBM)
Specialties: JOINKEYS, FINDREP, WHEN=GROUP, ICETOOL, Symbols, Migration
DFSORT is on the Web at:
www.ibm.com/storage/dfsort