Date: Fri, 21 Jun 2013 02:31:29 -0700 (PDT)
From: rawi <only4com@web.de>
To: pgsql-sql@postgresql.org
Message-ID: <1371807089696-5760297.post@n5.nabble.com>
In-Reply-To: <22495.1371135398@sss.pgh.pa.us>
References: <1371123556877-5759021.post@n5.nabble.com>
 <22495.1371135398@sss.pgh.pa.us>
Subject: Re: Index Usage and Running Times by FullTextSearch with prefix
 matching
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Tom Lane-2 wrote
> rawi &lt;

> only4com@

> &gt; writes:
>> And querying: FTS with prefix matching:
> 
>> SELECT count(a)
>> FROM t1
>> WHERE a_tsvector @@ to_tsquery('aaa:* & b:* & c:* & d:*')
> 
>> (RESULT: count: 619)
>> Total query runtime: 21266 ms.
> 
> FWIW, I get fairly decent performance for cases like this in HEAD
> (at least with a GIN index; GIST seems much less able to do well with
> short prefixes).  What PG version are you testing?

Last tests with PG 9.2:

Whereas the "whole words" full text search stays at ~350ms for 900,000
records I tryed the number of records, which are becoming to make one
suffer, querying for prefixes:

RECORDS		RUNTIME (ms)
10,000		13
100,000		81
200,000		172
400,000		7,284
900,000		20,888

Regards, Rawi


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