Re: reading a big file

["James W. Kilgore" <qappdsn@xxxxxxx>]

boothm@earth.goddard.edu wrote: 
<snip> 
> The file I am concerned with has 5 million records.  I want to go through
> this file making selections based upon choices made for several fields.
> Normally I would use the RPG cycle and bang down through the file (no K),
> making the selection tests with the most limiting choice first, and as
> soon as a record fails, goto end of cycle.  
<snip> 
> I've done this a lot on smaller files and smaller machines.  It offers a
> real easy front-end for the user and is flexible.
> 
Use the same front end, but since you have no index, construct an
OPNQRYF command instead, the DBMS will read through the file and filter
without having to pass every record to a HLL.

Study the request patterns, maybe have requests logged to a file for
later analysis, and build at least the most common filtering request as
a logical.

Hope you weren't looking for 2 sec response time. =:-o

If you are building a subfile, use page-at-a-time building, optimize
your OPNQRYF to *FIRSTIO...good luck.
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