From: NSO <nso@fmf.vtu.lt>
To: Sean Davis <sdavis2@mail.nih.gov>
Cc: pgsql-performance@postgresql.org
Subject: Re: Bytea poor performance
Date: Sat, 15 Oct 2005 17:00:09 +0300 (EEST)
Message-ID: <17363.81.7.89.65.1129384809.squirrel@fmf.vtu.lt> (raw)
In-Reply-To: <BF767F0C.10CEA%sdavis2@mail.nih.gov>
References: <17260.81.7.89.65.1129382454.squirrel@fmf.vtu.lt>
<BF767F0C.10CEA%sdavis2@mail.nih.gov>
Hello,
How about some explain analyze output?
Explain analyse select * from files where nr > 1450
"Index Scan using pk on files (cost=0.00..3.67 rows=50 width=36)
(actual time=0.000..0.000 rows=50 loops=1)"
Have you done a full vacuum lately? How about reindexing?
Yes, I did reindexing and vacuum full just before query..
> On 10/15/05 9:20 AM, "NSO" <nso@fmf.vtu.lt> wrote:
>
>> Hello,
>>
>> I am trying to select form table with bytea field. And queries runs very
>> slow.
>> My table:
>> CREATE TABLE files (file bytea, nr serial NOT NULL) WITH OIDS;
>>
>> Query:
>> select * from files where nr > 1450
>>
>> (I have total 1500 records in it, every holds picture of 23kB size)
>> Query runs very long:
>> Total query runtime: 23625 ms.
>> Data retrieval runtime: 266 ms.
>> 50 rows retrieved.
>>
>> explain:
>> Index Scan using pk on files (cost=0.00..3.67 rows=50 width=36)
>> Index Cond: (nr > 1450)
>>
>> Is it possible to do something with it? or it is normal? Our server is
>> fast, and all other tables work fine..
>
> How about some explain analyze output? Have you done a full vacuum
> lately?
> How about reindexing?
>
> Sean
>
>
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To: pgsql-performance@postgresql.org
Cc: nso@fmf.vtu.lt, sdavis2@mail.nih.gov
Subject: Re: Bytea poor performance
In-Reply-To: <17363.81.7.89.65.1129384809.squirrel@fmf.vtu.lt>
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