From: Luke Lonergan <llonergan@greenplum.com>
To: Laszlo Nagy <gandalf@designaproduct.biz>
To: pgsql-performance@postgresql.org
Subject: Re: tsearch2 question (was: Poor performance on seq
Date: Tue, 12 Sep 2006 11:36:10 -0700
Message-ID: <C12C4C2A.30B55%llonergan@greenplum.com> (raw)
In-Reply-To: <4506E7EC.8080605@designaproduct.biz>
Lazlo,
On 9/12/06 10:01 AM, "Laszlo Nagy" <gandalf@designaproduct.biz> wrote:
> zeusd1=> explain analyze select id from product_search where name_desc
> like '%Mug%';
> QUERY PLAN
> ------------------------------------------------------------------------------
> ------------------------------------------
> Seq Scan on product_search (cost=0.00..54693.34 rows=36487 width=8)
> (actual time=20.036..2541.971 rows=91399 loops=1)
> Filter: (name_desc ~~ '%Mug%'::text)
> Total runtime: 2581.272 ms
> (3 rows)
>
> The total runtime remains below 3 sec in all cases.
By creating a table with only the name field you are searching, you have
just reduced the size of rows so that they fit in memory. That is why your
query runs faster.
If your searched data doesn't grow, this is fine. If it does, you will need
to fix your disk drive OS problem.
- Luke
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To: pgsql-performance@postgresql.org
Cc: llonergan@greenplum.com, gandalf@designaproduct.biz
Subject: Re: tsearch2 question (was: Poor performance on seq
In-Reply-To: <C12C4C2A.30B55%llonergan@greenplum.com>
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