Re: index rebuilding...

Don,

It's perfectly okay to say that the article that comes up is one of yours - after all, a user who is searching google in their local language may have something completely different as the second hit.

A couple of points, by the way:

Oracle B-tree indexes are balanced: every leaf is the same height from the root, it is not possible for some leaf blocks to have height three and others to have height four. (This is an error I used to make as well, before I sat down and though about block splits).

The 'gets per key' is affected by the typical number of table rows per key - so rebuilding the index because it exceeds any particular level is unlikely to be of any benefit. The formula for this column is roughly:

    height + half of (rows in index / distinct keys in index)

I can't think why the factor of a half has been included though.

--
Regards

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

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Don Burleson wrote in message
<998d28f7.0301310721.3c724ec_at_posting.google.com>...


>Hi,

>

>Do a Google search on "oracle index rebuild".

>

>The second hit has a good article on the topic.