Thursday, November 10, 2022


Note: "Then & Now" (T&N) is a new version of what used to be the "Oldies but Goodies" (OBG) series. To demonstrate the superiority of a sound theoretical foundation relative to the industry's fad-driven "cookbook" practices, as well as the evolution/progress of RDM, I am re-visiting my 2000-06 debunkings, bringing them up to my with my knowledge and understanding of today. This will enable you to judge how well my arguments have held up and appreciate the increasing gap between scientific progress and the industry’s stagnation, if not outright regress.

This is a re-published series of several DBDebunk 2001 exchanges on Simon Wlliams' so-called "Associative Model of Data" (AMD), academic claims of its superiority over RDM ("The Associative Data Model Versus the Relational model") and predictions of the demise of the latter ("The decline and eventual demise of the Relational Model of Data").

Part 1 was an email exchange among myself (FP), Chris Date (CJD) and Lee Fesperman (LF) in reaction to Williams' claims that started the series. Part 2 was my response to a reader's email questioning our dismissal of Williams's claims. Part 3 was my email exchange with Williams where he provided his definition of a data model on which I conditioned any discussion with him and I debunked it. Part 4 is my response to a reader's comments on my previous posts in the series.

Thursday, November 3, 2022


09/19/23: For the latest on 1NF see: FIRST NORMAL FORM - A DEFINITIVE GUIDE


Note: In "Setting Matters Straight" posts I debunk online pronouncements that involve fundamentals which I first post on LinkedIn. The purpose is to induce practitioners to test their foundation knowledge against our debunking, where we explain what is correct and what is fallacious. For in-depth treatments check out the POSTS and our PAPERS, LINKS and BOOKS (or organize one of our on-site/online SEMINARS, which can be customized to specific needs). Questions and comments are welcome here and on LinkedIn.

(Continued from Part 2)

In this part we set matters straight about first normal form (1NF)

What's right/wrong about this database picture?

“A relation is in first normal form (1NF) if (and only if):
  • Each attribute contains only one value.
  • All attribute values are atomic, which means they can’t be broken down into anything smaller.
In practice, 1NF means that you should not have lists or other composite structures as attribute values. Below is an example of a relation that does not satisfy 1NF criteria:This relation is not in 1NF because the courses attribute has multiple values.

 Jane Smith       Databases, Mathematics
 John Lipinsky    English Literature, Databases
 Dave Beyer       English Literature, Mathematics

To transform this relation to the first normal form, we should store each course subject as a single value, so that each student-course assignment is a separate tuple.”
View My Stats