Re: Maximum height of an Oracle B-tree index

  • From: "Jonathan Lewis" <jonathan@xxxxxxxxxxxxxxxxxx>
  • To: <oracle-l@xxxxxxxxxxxxx>
  • Date: Sat, 27 Mar 2004 15:00:29 -0000


I've just written a new script to prove
the point.  It takes a couple of seconds
to run on 9.2 and bombs out with
    ORA-00600 [6051]
when you hit the blevel = 24 / height = 25

So whatever the reason, the documentation
is correct.

(The script doesn't fail on 10.1, because the
leaf-block split algorithm seems to have changed)


Jonathan Lewis

The Co-operative Oracle Users' FAQ

April 2004 Iceland
June  2004      UK - Optimising Oracle Seminar

----- Original Message ----- 
From: "Lex de Haan" <>
To: <oracle-l@xxxxxxxxxxxxx>
Sent: Saturday, March 27, 2004 1:59 PM
Subject: RE: Maximum height of an Oracle B-tree index

: I should have looked in my own documentation, of course -- thanks for the
: correction Jonathan...
: kdxcolev is indeed part of each branch or leaf index block, and it is UB1.
: also found the same note, saying that the max value is 23, so we have max
: levels (0 thru 23) but unfortunately, I don't have an explanation why :-(

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