From: Tom Lane <tgl@sss.pgh.pa.us>
To: Dan Harris <fbsd@drivefaster.net>
Cc: pgsql-performance@postgresql.org
Subject: Re: Query tuning help
Date: Sun, 08 May 2005 22:28:51 -0400
Message-ID: <15734.1115605731@sss.pgh.pa.us> (raw)
In-Reply-To: <6f4a543a2fbd348c7e82876b8e477600@drivefaster.net>
References: <924ac6c029f5453c442eacdda06b132c@drivefaster.net>
<200505091051.14689.mr-russ@pws.com.au>
<6f4a543a2fbd348c7e82876b8e477600@drivefaster.net>
Dan Harris <fbsd@drivefaster.net> writes:
>> -> Index Scan using ea1 on ea (cost=0.00..2736.43 rows=42 width=47) (actual time=2.085..2.309 rows=2 loops=473)
>> Index Cond: ((ea.incidentid)::text = ("outer".incidentid)::text)
>> Filter: (((recordtext)::text ~~ '%RED%'::text) OR ((recordtext)::text ~~ '%CORVETTE%'::text))
> Doesn't that mean it was using an index to filter?
No. The "Index Cond" shows it is using the index only for the join
condition. A "Filter" is an additional filter condition that happens to
get applied at this plan node --- but it'll be applied to every row the
index finds for the index condition.
regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, fbsd@drivefaster.net
Subject: Re: Query tuning help
In-Reply-To: <15734.1115605731@sss.pgh.pa.us>
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