Re: - Mailing list pgsql-performance

From Hannu Krosing
Subject Re:
Date
Msg-id 1038863893.1942.3.camel@rh72.home.ee
Whole thread Raw
In response to Re:  (<typea@l-i-e.com>)
List pgsql-performance
typea@l-i-e.com kirjutas T, 03.12.2002 kell 01:45:
> Explains were posted previously, but I'll do a couple more.
>
> At its simplest, this takes 30 seconds:
>
> explain select article.* from article where lower(text) like '%einstein%';
> NOTICE:  QUERY PLAN:
>
> Seq Scan on article  (cost=0.00..1155.01 rows=1 width=216)

searches with LIKE use indexes only when the like expression starts
with a string (like 'einstein%') and even then only if in C locale.

You should check out some real full-text index add-ons, like contrib/tsearch or
construct your own using your imagination plus contrib/intarray and contrib/intagg  :)

---------------
Hannu






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