Re: This same query - diffrerent time to execute...

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Thu, 25 Apr 2002 08:59:34 +0100
Message-ID: <1019721491.23053.0.nnrp-14.9e984b29@news.demon.co.uk>

It would be appropriate to tell us how much difference - 3 seconds to 15 minutes is worth looking at 0.5 seconds to 0.51 seconds is not.

First step in your investigation - check the execution path. It is possible that by forcing Oracle to do ANSI comparison instead of binary comparison you are effectively disabling and index which helps to accelerate the BINARY path.

--
Jonathan Lewis
http://www.jlcomp.demon.co.uk

Author of:
Practical Oracle 8i: Building Efficient Databases

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Ariel wrote in message ...


>Hello!

>

>I got this by using statements before "select" query.

>

>ALTER SESSION SET NLS_COMP = ANSI (does slower execute)

>ALTER SESSION SET NLS_COMP = BINARY   (does faster execute)

>

>Why?

>

>I use 8.1.7 EE.

>

>

>

Received on Thu Apr 25 2002 - 02:59:34 CDT