Re: Query is slow when executing in procedure

From: Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com>
To: ramasubramanian <ramasubramanian(dot)g(at)renaissance-it(dot)com>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: Query is slow when executing in procedure
Date: 2009-11-24 06:10:54
Message-ID: 162867790911232210u111b1609i1252dd14e44e4e07@mail.gmail.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-performance

2009/11/24 ramasubramanian <ramasubramanian(dot)g(at)renaissance-it(dot)com>:
> Dear all,
>     The query is slow when executing in the stored procedure(it is taking
> around 1 minute). when executing as a sql it is taking 4 seconds.
> basically i am selecting the varchar column which contain 4000 character. We
> have as iindex on the table. We have analyzed the table also. What could be
> the reason. How to improve it?

Hello

use a dynamic query - plpgsql uses prepared statements. It use plans
generated without knowledge of real params. Sometime it should to do
performance problem. EXECUTE statement (in plpgsql) uses new plan for
every call (and generated with knowledge of real params) - so it is a
solution for you.

http://www.postgresql.org/docs/8.4/static/plpgsql-statements.html#PLPGSQL-STATEMENTS-EXECUTING-DYN

Regards
Pavel Stehule

>
> Thanks in Advance
> Ram

In response to

Responses

Browse pgsql-performance by date

  From Date Subject
Next Message A. Kretschmer 2009-11-24 06:15:52 Re: Query is slow when executing in procedure
Previous Message ramasubramanian 2009-11-24 05:38:20 Query is slow when executing in procedure