RE: Chaining with a very large file

My plan at this point would be to juse handle it via straight RPG access, 
via of two possible logical files depending on the first value. 

It would be interesting to know how long it would take to locate the record 
with the chain....1 sec 10 sec , etc., especially since this will be an 
interactive process or at least one portion of it would be.

Thanks for the tip, I know sql is out of the question for a file this size 
and the machine we have.

Douglas


On Wed, 1 Feb 2006 09:55:44 -0600 , DeLong, Eric wrote
> Douglas,
> 
> As long as you don't do things that try to build access paths dynamically
> 
> (such as SQL or OPNQRYF) and you stick to keyed access in RPG, you 
> should be fine.  I would think that breaking this down into smaller 
> units would only increase the hassles of managing these file objects,
>  especially if they'll all be joined into a common access path anyway....
> 
> If you need to access this monster file via SQL, it's important to ensure
> that you have the correct indexes already built.  Performance tuning 
> in SQL is sometimes a bit like sorcery or alchemy...  You might see 
> what you want today, but tomorrow it won't work the same....
> 
> Eric DeLong
> Sally Beauty Company
> MIS-Project Manager (BSG)
> 940-297-2863 or ext. 1863
> 
> -----Original Message-----
> From: rpg400-l-bounces@xxxxxxxxxxxx
> [mailto:rpg400-l-bounces@xxxxxxxxxxxx]On Behalf Of Douglas W. Palme
> Sent: Wednesday, February 01, 2006 8:08 AM
> To: RPG Group
> Subject: Chaining with a very large file
> 
> we may be faced with having to allow an interactive program to do a 
> chain to
> 
> a very large file; one with approximately 1.1 billion records and a 
> file size of approximately 9.7gb of disk space.
> 
> Are there any performance issues that I should take into 
> consideration?  Should I consider breaking the data down into 
> multiple files?
> 
> The file will have a total of three numeric fields, all packed, 5 
> digits for
> 
> the first two and 4 digits for the third.
> 
> Suggestions, thoughts, helpful hints.....would all be appreciated.
> 
> If you bought it, it was hauled by a truck - somewhere, sometime.
> 
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If you bought it, it was hauled by a truck - somewhere, sometime.