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From: Tom Lane <tgl@sss.pgh.pa.us>
To: rawi <only4com@web.de>
cc: pgsql-sql@postgresql.org
Subject: Re: Index Usage and Running Times by FullTextSearch with prefix
 matching
In-reply-to: <1371123556877-5759021.post@n5.nabble.com>
References: <1371123556877-5759021.post@n5.nabble.com>
Comments: In-reply-to rawi <only4com@web.de>
 message dated "Thu, 13 Jun 2013 04:39:16 -0700"
Date: Thu, 13 Jun 2013 10:56:38 -0400
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rawi <only4com@web.de> 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?

			regards, tom lane


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