Re: OPNQRYF Vs Logical Files

[PaulMmn <PaulMmn@xxxxxxxxxxxxx>]

>Venu wrote (in part):
>
>     In one of my jobs, I will be processing data from a physical file say
>File1. File1 has 3 members. I will select data from the 2 out of 3 members.
>Also I have a select criteria (select where File1.field1 = xxxx) to process
>the records.
>
>     At present I've created a Logical file over the two members of the PF
>with the Select criteria specified in DDS of the LF. This LF I am using in
>my RPG. But the job processes 1.3 million records from both the members.
>This job runs in batch.
>
>     Our people are suggesting to replace the LF with a OPNQRYF in a driver
>CL. So after discussing the pros and cons, I have 2 alternate ways :
>


I'd say bite the bullet just once, and create 3 logical files.  Each will
be a join logical across 2 of the 3 members (1+2, 2+3, and 1+3).  The
select/omit will process once as the LF builds.

When your job runs, select the proper LF and read the records sequentially
in the proper sequence.

This will be beneficial especially if the number of records to be processed
includes most of the records in the file.


--Paul E Musselman
PaulMmn@ix.netcom.com


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