Re: index rebuilding...

Daniel,

I think that's the thread where someone suggested I was talking rubbish - and where I subsequently sat down and thought it through and decided that I was talking rubbish. I think you'll even find my retraction and explanation further on in that thread.

--
Regards

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

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DA Morgan wrote in message <3E3B0D3F.9916449D_at_exesolutions.com>...


>

>Just went through my files and found a posting by Jonathan from 23

May, 2002


>subject title "unbalance indexes --common widsom?". And I quote:

>

>"No matter how perfectly an index is maintained, it will always be

possible to


>ensure that you can get it to a state where either just one 3rd level

node has


>split to produce an "imbalance" or (the only possible alternative)

every 3rd


>level node has to split to leave the index half-populated if you want

"balance"


>- i.e. every leaf has to be at the fourth level.

>

>The important point about balance b-trees is that no leaf is MORE

THAN ONE level


>deeper that every other leaf."

>

>(even the above misspelling accurately copied).

>

>So unless Jonathan has changed his mind ... my recollection is

correct.


>

>Jonathan?

>