RE: SQL select by date

["Elvis Budimlic" <ebudimlic@xxxxxxxxxxxxxxxxxxxxxxxxx>]

Avoid concatenation, as query optimizer does not like to use indexes with
derived fields.
Perhaps you could do something like 
WHERE POSTCY = '2004' AND POSTMM = '11' AND POSTDD = '27'?

That should use the existing index.  Or perhaps build new 3 field index.
STRDBG before you run it and see what query optimizer suggests.

Elvis


-----Original Message-----
From: midrange-l-bounces@xxxxxxxxxxxx
[mailto:midrange-l-bounces@xxxxxxxxxxxx] On Behalf Of Rich Duzenbury
Sent: Friday, September 24, 2004 12:41 PM
To: ISeries Mailing List
Subject: SQL select by date

Hi,

I want to select some records via SQL that contain a transaction posting
date via a date range.  Unfortunately, the dates are stored in
components: 

POSTCY  4,0
POSTMM  2,0
POSTDD  2,0

In order to do a range selection in a where clause, the date fields must
be concatenated together in some way.

This file has millions of records, and there is an index by POSTYY,
POSTMM, POSTDD.

What is the correct (efficient) way that will hopefully use the existing
index?  

Thanks.
--
Regards,
Rich

Current Conditions in Des Moines, IA
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