RE: Working with tables, best method -- RPG400-L

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Subject: RE: Working with tables, best method
From: "Walden H. Leverich" <WaldenL@xxxxxxxxxxxxxxx>
Date: Fri, 15 Feb 2008 11:31:18 -0500
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However, the ordering of the tables can
have significant impact, especially if you have additional filtering
criteria. Which makes sense; if you have a file with order numbers to
process, you don't read every record in the order file and chain to the

list of orders to see if you should process it; you read the orders to
process and chain to the order file.

Yes, but the better the query-optimizer the less I as a programmer have
to worry about that. The optimizer should know from statistics that the
order-master has 1M rows and the orders-to-process file has 10 rows and
reorder the query to do the select in the right way.

Statistics can make or break an optimizer.

-Walden

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Re: Working with tables, best method , Joe Pluta

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