From: | Martijn van Oosterhout <kleptog(at)svana(dot)org> |
---|---|
To: | Lars Kanis <kanis(at)comcard(dot)de> |
Cc: | pgsql-hackers(at)postgresql(dot)org |
Subject: | Re: Problems with index-scan on regexp in 8.1 |
Date: | 2005-11-07 13:13:13 |
Message-ID: | 20051107131313.GC841@svana.org |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-hackers |
On Mon, Nov 07, 2005 at 07:50:20AM +0100, Lars Kanis wrote:
> We're using Postgres 8.0.2 on SuSE10.0 (64-Bit). Tests on 8.1 beta 4 have
> shown no problems but this one:
>
> SELECT * FROM mitglieder WHERE lower(vorname::text)='lars'
>
> does a bitmap-index-scan like this:
Check your locales. For non-ASCII locales the normal shortcuts for
regex optimisation can't apply. Evidently your old installation uses a
different locale from your new one.
You should be able to make this work by declaring your index with
"text_pattern_ops", like so:
CREATE INDEX myindex ON mytable(mycolumn text_pattern_ops);
Hope this helps,
--
Martijn van Oosterhout <kleptog(at)svana(dot)org> http://svana.org/kleptog/
> Patent. n. Genius is 5% inspiration and 95% perspiration. A patent is a
> tool for doing 5% of the work and then sitting around waiting for someone
> else to do the other 95% so you can sue them.
From | Date | Subject | |
---|---|---|---|
Next Message | Andrew Dunstan | 2005-11-07 13:39:24 | Re: Old interfaces directory in CVS tree? |
Previous Message | Alvaro Herrera | 2005-11-07 12:19:40 | Another pgindent gripe |