From: Peter Eisentraut <peter_e@gmx.net>
To: Joost Kraaijeveld <J.Kraaijeveld@askesis.nl>
Subject: Re: What should this query match?
Date: Wed, 14 Sep 2005 12:48:24 +0200
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Am Mittwoch, 14. September 2005 11:54 schrieb Joost Kraaijeveld:
> Why do the following queries return the same count (may be related to
> the first question)
>
> SELECT COUNT(*) FROM customers
> WHERE lower(lastName) < lower('Jan%')
>
> SELECT COUNT(*) FROM customers
> WHERE lower(lastName) <= lower('Jan%')

These queries should return the same answer if the query does not contain the 
value 'Jan%' (or differently capitalized versions).  I suspect that you are 
actually attempting to use % as a wild card, but none of your queries use a 
pattern matching operator, so I'd go back and check if your queries really 
are what you think they should be.

-- 
Peter Eisentraut
http://developer.postgresql.org/~petere/