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From: Gregory Stark <stark@enterprisedb.com>
To: "Andreas Joseph Krogh" <andreak@officenet.no>
Cc: <pgsql-sql@postgresql.org>
Subject: Re: PG won't use index on ORDER BY <expression>
In-Reply-To: <200708092238.46284.andreak@officenet.no> (Andreas Joseph Krogh's
	message of "Thu, 9 Aug 2007 22:38:46 +0200")
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"Andreas Joseph Krogh" <andreak@officenet.no> writes:

> Ooops, just fugured that out. But - it still doesn't use the index if I remove 
> the "varchar_pattern_ops". I solved it by adding a function:

Hm, well it does for me, you would have to post your explain analyze to see
what's going on.

> Another question then: Why doesn't "varchar_pattern_ops" handle ordering? This 
> means I need 2 indexes on the columns I want to match with LIKE and ORDER BY. 
> Just doesn't seem right to need 2 "similar" indexes...

If you initd in the C locale you only need one index. In other locales the
collation order and the pattern order are different.

-- 
  Gregory Stark
  EnterpriseDB          http://www.enterprisedb.com