Path: utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!uunet!cimshop!davidm From: cimshop!davidm@uunet.UU.NET (David S. Masterson) Newsgroups: comp.databases Subject: Re: Relational Databases Message-ID: Date: 11 Jun 91 01:16:24 GMT References: <6822@vela.acs.oakland.edu> <1991Jun07.063749.7904@chinet.chi.il.us> <1991Jun08.124337.29813@uvmark.uucp> Sender: davidm@cimshop.UUCP Distribution: comp Organization: Consilium Inc., Mountain View, California Lines: 31 In-reply-to: jim@uvmark.uucp's message of 8 Jun 91 12:43:37 GMT >>>>> On 8 Jun 91 12:43:37 GMT, jim@uvmark.uucp (Jim Todhunter) said: Jim> A relational database does NOT need to be normalized. In fact, some of Jim> the most interesting current research is the area of NFNF (non first Jim> normal form) relational models. This is a very active area of Jim> investigation because there are serious deficiencies in the first normal Jim> form model. While Codd dismisses NFNF and OO model out of hand, most Jim> others, including Date, do not share his view. (It is interesting to Jim> note that CODD's recent book reads very much like a dinosaur's defense of Jim> his raison d'etre.) NFNF models can also use indices. The truth is Jim> normalization is merely a convenience for that database theorist, making Jim> the mathemetical proofs easier. Hmmm, I'm interested. What are the deficiencies in first normal form? Are NFNF models processable with relational algebra/calculus? While I certainly think Codd could have been more complete in his book, he does make a lot of good points. For instance, he doesn't dismiss the OO model as easily as he does the UR or BR models, but rather indicates that it has promise once it answers some of the more difficult database management questions. I have always had difficulty in seeing the difference between a complete OODBMS and a relational database with abstract data types (the one unsurety I have is the prospect of multidimensional relations that this opens up). -- ==================================================================== David Masterson Consilium, Inc. (415) 691-6311 640 Clyde Ct. uunet!cimshop!davidm Mtn. View, CA 94043 ==================================================================== "If someone thinks they know what I said, then I didn't say it!"