Re: RE: How does Oracle keep B-tree indexes to 3 levels?

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Thu, 19 Feb 2004 09:33:52 -0000
Message-ID: <000c01c3f6cb$7e93df40$6702a8c0@Primary>

It is possible that the 67% you are quoting is the figure given for the worst-case scenario on b*trees, which is textbook stuff. (Although Oracle claims B*Trees in their manuals somewhere, they aren't using them, they are using B+trees).

The 69% comes from a paper on Fringe Analysis of 2-3 trees, and is a result that applies to generic b-trees.

Of course, it is possible that you were at college many years after I was, so fringe analysis may be a standard on the sylllabus now.

Regards

Jonathan Lewis
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Original Message ----- From: <ryan.gaffuri_at_cox.net> To: <oracle-l_at_freelists.org> Sent: Wednesday, February 18, 2004 12:53 PM Subject: Re: RE: How does Oracle keep B-tree indexes to 3 levels?

the 67% percent full is actually in my college textbook. so its probably = somewhat standard. =

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Received on Thu Feb 19 2004 - 03:33:52 CST