Re: ORDER BY performance problem

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Tue, 10 Aug 1999 22:33:05 +0100
Message-ID: <934322022.5459.0.nnrp-10.9e984b29@news.demon.co.uk>

Could you tell us the version of Oracle, how fast is 'really fast'
how big a difference is 'really big'

One possibility it that the ORDER encourages Oracle to use a different access path to do an order by through a driving index rather than through a sort - and this may actually be a very inefficient path compared to the path used for the unordered query.

Have you tried explain plan on both queries ?

Jonathan Lewis
Yet another Oracle-related web site: www.jlcomp.demon.co.uk

Franz Mueller wrote in message <37aed8a9.26184190_at_news.salink.net>...
>Hi,
>
>I have a performance problem with a query that ends with "ORDER BY .."
>Without the ORDER BY it runs really fast. The difference is really big
>(on an answer set with 200 rows). Is there a way to speed up this kind
>of query?
>
>Franz
Received on Tue Aug 10 1999 - 16:33:05 CDT