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Re: GiST index slower than seqscan - Mailing list pgsql-general

From Teodor Sigaev
Subject Re: GiST index slower than seqscan
Date
Msg-id 444820BB.9090007@sigaev.ru
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In response to GiST index slower than seqscan  (CG <cgg007@yahoo.com>)
Responses Re: GiST index slower than seqscan
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> In case you're unfamiliar with this particular horse, I'm using ltree to create
> a full text index on some <= 50 char long fields for a lookup table. The idea
> was to be able to tear through tons of data quickly finding case insensitive
> substring matches.
>

Why it is a ltree, not a tsearch?


>          Index Cond: (search_vector ~ '*.6.6.9.3.4.4.*'::lquery)

That's the problem. Queries which begin with '*' will be slow enough...



Try to reduce SIGLENINT in tsearch2/gistidx.h up to 8 (do not forget reindex !!)
and try it....

--
Teodor Sigaev                                   E-mail: teodor@sigaev.ru
                                                    WWW: http://www.sigaev.ru/

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