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.
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Then: MORE ON WILLIAMS'S(?) AMD
(originally published August 2002)
“While browsing the web I came across your site and in particular the comments regarding Simon Williams and his Associative Database system "Sentences".Given his lack understanding of data and relational fundamentals reflected by his communications to date, I am very skeptical of progress along these lines for a variety of reasons.
You may be interested to know that the concepts Williams now claims as his own were published on the web by me around eight years ago on my web site, first at Cityscape.co.uk (now defunct) then at Pipex Dial (dspace.dial.pipex.com) when that acquired Cityscape. I started to jot some ideas down about nine years ago as the basis of a book; see the attached document. At the time I was interested in AI and thought that the AI attempts of the day were flawed in the way they handled data. I thought that in order to approach a human capability there needed more thought on the way data was stored, and that the key to AI was not information processing, but information storage. You may also be interested that I was an ORACLE Development Team Manager at the time (as well as doing an SSADM qualification) so was reasonably informed about data structures and the relational data model.
If an information storage system could mimic the way we stored information then that information would become processable in similar ways to the ways in which we think. Thus I felt that processes like leaps of intuition, creative and lateral thinking are consequences of the way in which we store information. To store data in conventional RDBMS structures fundamentally makes such processes difficult and so AI needed to develop new storage structures.
I therefore proposed Associative storage as a storage model, which made possible AI type information processing. I got as far as designing two basic necessary structures; a data or atom structure, which stored all the atoms of information; and a link table, which stored the links between these atoms. I wasn't sure whether the associative links should have attributes (e.g., the type of association they were or whether to store this again by association). At the time I had difficulty getting hold of any database programming add-ons to try out my ideas, though eventually I got the Borland Paradox Engine in March 1994.
Since I didn't develop these ideas further I am happy to wish Williams well in his use of them, but I am not happy for him to claim that he invented them. After reading your comments I looked at his website and he says he is claiming US patent rights on these ideas. It is possible he did independently come up with similar ideas to me, but I believe I was first (in 1992/1993) and if anyone has an archive of PIPEX from 1994 they will see this. I also have a notebook in which I jotted this all down, which should be forensically dateable too.
As part of my dabblings around this I started toying with the idea of creating a company called Alogic (short for Associative Logic). I have use the email address achapman.alogic@virgin.net for around four years and my website on Cityscape and Pipex Dial was headed with an ALogic logo. I also hosted a Local Government web directory called the "Local Gov One stop Shop" run under this Alogic banner.
Therefore I think I can prove my case on this. Up until now I haven't been too bothered, since my deliberations on this concluded that there were a series of problems with taking it further; one of which was the problems in representing the data physically in a way that was more efficient than conventional data structures. I do object to Williams’s arrogance, though, as if he has come up with something that is totally original, without crediting his sources. I would also object to being prevented from talking about something I thought up because he has the copyright on my ideas; whether or not they are flawed.”
“I am quite happy for you to post what I sent you the other day. I posted my original thoughts in a spirit of open science, for others to use and build on, if they wanted to. I expect the usual quid pro quo, that if people build on your ideas, they at least have the courtesy to acknowledge they are doing so. I was prepared to give Williams the benefit of the doubt, that he independently thought this all up. But the more I learn of him the less likely this seems.Whatever its pros and cons, AMD does not seem to be a 'data model' in the sense in which it was defined by Codd and of which the the RDM is an example; there is a lot of confusion as to models out there (see Date's Models, Models Everywhere, Nor Any Time to Think). Williams does not seem to comprehend this, even when he is using others' definition for what a data model is. That indicates a more serious problem.
I appreciate your skepticism, which is another reason why I didn't feel like confronting Williams. As I said in my previous email I felt there were holes in the 'Associative Model' (if I can be so grandiose), which meant I didn't particularly want to be identified with it, and certainly didn't want to be in the position of defending it against experts.”
And Now
I do not have much to add except to say that one of the core objectives of the RDM is physical independence (PI) -- the insulation of applications and users from physical implementation details, of which storage methods are a component. Storage is, thus, part of the implementation, not of the data model.
I suspect that when he referred to "storage methods" the reader actually meant database technology, lumping together the logical and physical aspects that induces the common logical-physical confusion (LPC): many in the industry consider database systems sheer physical stores of data, not logical inference systems. I do not know much about AI, but I suspect storage bears the same relationship to it as to databases.
Williams claimed that AMD is a data model, which is a purely logical construct. He did not specify what in his model replaces the theoretical foundation of the RDM -- simple set theory expressible in first order predicate logic (SST/FOPL) and the relationsl algebra (RA) and, thus, what guarantees correctness (semantic consistency and logical validity) as well as the other benefits of the RDM).
(Continued in Part 5)
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