Re: index rebuilding...

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Sun, 2 Feb 2003 09:55:02 -0000
Message-ID: <b1ipul$gtj$1$8300dec7@news.demon.co.uk>

Of course, this does mean that Oracle doesn't use B*Trees, as it's manuals have claimed since at least 5.1 - it uses a version of B+trees.

Correct me if I'm wrong, but aren't B*trees supposed to redistribute leaf entries to adjacent blocks without doing a split if certain conditions are met - and this is something that Oracle never does.

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Jonathan Lewis
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Peter J. Holzer wrote in message ...


>

>B+trees push all the data down to the leaf nodes and keep only

pointers


>to other nodes in the higher level nodes.

>

>B*trees are like b+trees, but use a modified split algorithm to keep

the


>nodes at least 2/3 filled.

>

Received on Sun Feb 02 2003 - 03:55:02 CST