This site is free. However, its maintenance demands time, effort and expense. If you deem it interesting and/or useful, please support the effort via purchases of BOOKS and PAPERS and/or contributions to keep it free.

The Problem

"[Current DBMS] deficiencies are, it seems to me, directly due to the widespread lack of understanding (not least on the part of vendors), of fundamental database principles. Certainly it is undeniable that they flout those principles in numerous ways. And the practical consequences are all too obvious. First, users must understand where the deficiencies lie. Second, they have to understand just why they are deficiencies. Third, they have to understand how to work around them. Fourth, they have to devote time and effort in persuading the vendors to remedy them.The trouble is, of course, users too tend to be unaware of those same fundamental principles and, hence, find themselves unable to carry out their side of the "contract" (a "contract" that should not have been allowed, or agreed to in the first place, of course). What is more, this sad state of affairs is not likely to change given the apparent lack of interest on the part of the trade press--itself unaware these same principles--in trying to improve matters." --C. J. Date

Data professionals and users are not familiar with the history and fundamentals of the database field. Consequently, technology is actually regressing!

The Solution

DATABASEDEBUNKINGS (DBDebunk) is an educational blog, the purpose of which is:

  • To make data fundamentals accessible to practicing data professionals and users; 
  • To correct myths and misconceptions about and explain the practical implications of data fundamentals -- concepts, principles and methods -- that are misused, abused, or are ignored in the industry;
  • By means of the McGoveran interpretation of his correct formalization pf Codd's true RDM -- distinct from the distortion that passes for it in the industry;
The target audience is anybody who interacts with data and databases who
  • Thinks critically and independently;
  • Prefers understanding to the "cookbook" approach and soundness to fads, fashion and expediency;
  • Appreciates the difference between education and tool training;

regardless of the DBMS used.

How to Use the DBDebunk Site

Since its inception, Blogger has had a 200 character limit on the set of labels per post and Google, as is its wont, does not bother to expand it. Moreover, there are more fundamental terms than can be practically included in the label list. Having looked for and failed to find a widget or programmatic solution, the only way around these limitations is to use acronyms and abbreviations as labels. It is cumbersome, but it expands searching and serves an educational purpose -- you can familiarize yourself with fundamental terminology. 

Labels and the FUNDAMENTALS Page

The FUNDAMENTALS page lists data fundamental terms with their acronyms or abbreviations, if any. The terms, abbreviations or acronyms that have labels on the label list are marked in red.

To find posts referencing a term of interest:

1. Look it up in the label list: 

  • Is it, or its acronym on the list?
  • If yes, search by it.If not, you may not recognize its acronym or abbreviation (unfortunately, Blogger does not allow to document what they stand for in the label list itself).

2. Look it up on the FUNDAMENTALS page: Is your term on it? 

  • If yes, is it red, or does it have a red abbreviation or acronym?

- If yes, do a label search by it; 

- If not, do a full term Blogger search. If not, try a Blogger search. If no luck, email me -- it may be worth adding a label.

  • If not, do a Blogger full term search.

For example, say you are looking for posts about logical-physical confusion -- the abbreviation is LPC and it has a label. If you know the abbreviation, you can look for it in the label list and search by it. If you don't, go to the FUNDAMENTALS page and look for your full term, which is listed in red with LPC as the label and do a label search.

Now, suppose you're looking for posts about disjunctive constraint, which does not have an abbreviation or label. You go to the FUNDAMENTALS page, where it is listed without an acronym and is not in red, so there is no label and you do a full term Blogger search.

Note very carefully, however:

  • For label searches the results are based on my judgment of the relevance/significance of the term in the post  (I may tag a post with a label even if the term is not referred explicitly, but I deem it implicitly significant). So you will end up with posts "curated" by me (so to speak). 
  • For Blogger searches, you will end up with all the posts with explicit references to the term, regardless of significance.

While the Blogger search option was always there, now there is also the correct terminology to guide the search and serve as a learning resource.

All 2017 and later posts and those earlier posts rewritten in 2017 for consistency with the McGoveran interpretation of the RDM were re-labeled. Only the new labels that remained the same as the old are guaranteed to work with pre-2017, not rewritten posts -- you can only use Blogger search.

A Dictionary of Data Fundamentals

Given the ample misuse and abuse of data fundamentals in the industry, a rigorous and comprehensive dictionary thereof -- one that

  • Is consistent with the McGoveran formalization and interpretation RDM and distinct from what passes for it in the industry;
  • Includes (a) conceptual terms and (b) formal logical terms;

has long been overdue.

What Data Professionals Say about DATABASEDEBUNKINGS

"First of all I would like to point out that I'm a big fan of your seminars. A couple of years ago I had the pleasure to attend the two sessions you delivered at the PASS conference in Denver and they opened my eyes. I started reading your book and ended up reading several books from Date and Darwen and, although I'm sure I still have a lot to learn, they changed completely my way of thinking about databases (and of doing training, even if the context of a course focused on a SQL product). The more I read, thinking also about the articles on your web site, the more I realize how the whole IT field needs to be educated about relational technology." --Gianluca H., Managing Director, Microsoft SQL Server MVP
"I love your writing (books, articles, site postings). You're a beacon of rationality in an irrational (and increasingly confused) industry, and I rely on your site to help settle and focus my mind - for example, after days "refactoring" (I'm always tempted to spell that with a U instead of an A) XML "data stores" here at work. Thank you." --Eric K., Senior Software Developer
"I just wanted to thank all of you folks at DBDebunk for giving me a reason to continue doing my job!! And for providing me a safe haven where I can be reassured that I am not out of my mind for trying so hard to do this "modeling thing" well. I am faced with the "dumbed down" masses daily--and have almost abandoned all hope. ... Thanks for giving me the shovel I so desperately need to dig out from under all their "knowledge"!!" --Patricia E., (Beleaguered) Principal  Architect.
"I have found your work immensely useful in understanding database principles. I and a few colleagues have spent the better part of two years implementing our own data storage platform, observing those principles as best we have been able to, with very satisfying results." --Jesper L., Ph.D.C.Sc., Head of Research & Development
"My brief comments are based on my appreciation for your efforts to raise the educational level within the database profession. It's certainly not that "path of least resistance" you might have instead chosen. In particular, your books have helped me a great deal in my database design work. PRACTICAL ISSUES IN DATABASE MANAGEMENT was especially good, especially once I found the errata to fix some problems I had on initial reading." --Keith L., Computer Software Consultant

Founder, Editor & Publisher

Fabian Pascal is an independent author, educator and consultant specializing in data fundamentals and the relational model. Author of three books and hundreds of articles for the trade press, he taught seminars at the business and academic levels and lectured extensively at industry events. Clients include IBM, Census Bureau, CIA, Apple, UCSF, Golden Gate University and IRS, among others. He has founded DBDebunk in 2000 and publishes the PRACTICAL DATABASE FOUNDATIONS and UNDERSTANDING THE REAL RDM series of PAPERS, all of which are dedicated to making data fundamentals accessible to data practitioners without compromising theoretical rigor -- a non-trivial task.

Contact: dbdebunker.at.gmail.com 

This site is free. However, its maintenance demands time, effort and expense. If you deem it interesting and/or useful, please support the effort via purchases of BOOKS and PAPERS and/or contributions to keep it free.

(Last updated Novermber 2021)


  1. Hi
    Where can I find
    Database Design, Relational Fidelity and SQL, Parts 1-4, www.dbdebunk.com

    1. The old dbdebunk site, archived @the Internet Archive.

      However, I recommend you stick to the current site -- most of the material has been revised--particularly the papers and my latest book.

  2. Thanks. I found what I wanted in the newer papers. I was chasing up a reference in THE DBDEBUNK GUIDE TO MISCONCEPTIONS ABOUT DATA FUNDAMENTALS .

  3. Hhhmmm. Can you pls tell me in what section of the book is that reference? If it's one to the old site I must correct it.

  4. Come on and be real: All know that there is an idiot at the helm. Americans, put yourselves together,


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