Re: clustering factor and uniqueness

From: Mladen Gogala <gogala_at_sbcglobal.net>
Date: Fri, 31 Mar 2006 05:21:53 GMT
Message-Id: <pan.2006.03.31.05.21.53.550008@sbcglobal.net>

On Thu, 30 Mar 2006 13:12:08 +0000, Richard Foote wrote:

>
> The clustering factor is simply used by the cost based optimizer to
> calculate the cost of accessing the table via the use of the specific index.

There is an excellent, if somewhat complex presentation on MiracleAS site:

http://www.miracleas.dk/images/upload/Docs/Richard%20Foote.pdf

This document explains clustering factor, among other things. It also shows how to dump index blocks and interpret those dumps. I've been long waiting for an opportunity to ask author to update it with the situations from ASSM tablespaces and 10g database (the article deals with 9.2). I'd love to see more detailed explanation of Oracle dumps and statuses. Please, consider yourself asked.

-- 
http://www.mgogala.com

Received on Thu Mar 30 2006 - 23:21:53 CST