From: Jonah H. Harris <jonah.harris@gmail.com>
To: theo@flame.co.za
Cc: pgsql-performance@postgresql.org
Subject: Re: Performance problems with prepared statements
Date: Wed, 10 Oct 2007 15:55:07 -0400
Message-ID: <36e682920710101255n5760a009v8fdbf42e4599f16f@mail.gmail.com> (raw)
In-Reply-To: <1192027540.2495.3.camel@localhost.localdomain>
References: <1192027540.2495.3.camel@localhost.localdomain>
On 10/10/07, Theo Kramer <theo@flame.co.za> wrote:
> When running the query directly from psql it returns the required rows
> in less than 100 milli-seconds.
>
> However, when using a prepared statement from my C application on the
> above query and executing it the query duration is as follows
> ...
> Row[s] = 25, Duration = 435409.474 ms
>
How are you timing it? Does it really take 435 seconds to complete?
Try the following in psql:
postgres# PREPARE yourplan (VARCHAR, INT, INT) AS
SELECT oid, * FROM calllog
WHERE calllog_mainteng = $1
AND calllog_phase = $2
AND calllog_self < $3
OR calllog_mainteng = $1
AND calllog_phase < 8
ORDER BY calllog_mainteng DESC,
calllog_phase DESC,
calllog_self DESC limit 25;
postgres# EXECUTE yourplan('124 ', 8, 366942);
--
Jonah H. Harris, Sr. Software Architect | phone: 732.331.1324
EnterpriseDB Corporation | fax: 732.331.1301
499 Thornall Street, 2nd Floor | jonah.harris@enterprisedb.com
Edison, NJ 08837 | http://www.enterprisedb.com/
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To: pgsql-performance@postgresql.org
Cc: jonah.harris@gmail.com, theo@flame.co.za
Subject: Re: Performance problems with prepared statements
In-Reply-To: <36e682920710101255n5760a009v8fdbf42e4599f16f@mail.gmail.com>
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