Re: Implementing trees in a relational database

From: --CELKO-- <71062.1056_at_compuserve.com>
Date: 30 Jul 2002 18:18:40 -0700
Message-ID: <c0d87ec0.0207301718.6427edd7@posting.google.com>

>> ... the paper on this at SIGMOD/PODS by Cohen, Kaplan and Milo
titles "Labeling Dynamic XML trees"

http://www.informatik.uni-trier.de/~ley/db/conf/pods/pods02.html#CohenKM02

It tries to come up with numbering schemes for trees that change a lot, because that is the weak spot of the numberting scheme. <<

I just let my ACM membership lapse! Oh well, maybe I can find a copy somewhere.

My approach to this problem in the nested set model is to use large gaps in the (lft,rgt) pair numbering instead of incrementing them. This trick destroys the property that (rgt - left +1)/2 = size of subtree rooted at this node, however.
I sitll need to test various formulas for computig the size of the gaps. Received on Tue Jul 30 2002 - 20:18:40 CDT