Foreword

by Professor Dr. Sjir Nijssen, CTO
PNA Group, The Netherlands

It gives me great personal pleasure to write this foreword. I have known Terry Halpin since 1986. As John Zachman has said about Terry, he is one of those people who is bigger than his reputation and far more humble than his contribution warrants. Terry is one of the most effective and dedicated authors of a new wave in knowledge engineering and requirements specification. I would like to classify ORM (Terry’s focus, called Object-Role Modeling) as a fact orientation approach. This by itself is already much broader than data modeling. It is my professional opinion, based on extensive experience during more than 40 years in business and academia, that fact orientation is the most productive data modeling approach, by far. This approach could be considered as a best business practice for SBVR (Semantics of Business Vocabulary and Business Rules), the standard adopted by the Object Management Group (OMG) on December 11,2007.

With fact orientation, it is useful to distinguish between structure and structuring. Both are important in practice and theory. With respect to structuring, one of the sub-processes is verbalization. Verbalization is a major and unique part of the CogNIAM and ORM methodology. This entered the fact orientation community in 1959, when I was training young people to plot the movements of airplanes in an area where radar could not yet see. In 1967 I got the chance of a professional lifetime. My manager said “| want to hire you, and you have only one mission: nearly every software professional in our company (Control Data Corporation, one of the most powerful computer companies in that period) is preoccupied with programming. I want you to ignore procedural programming, and concentrate on the data underlying all programming”.

During the seventies, conceptual modeling—of which ORM is an instance—was developed primarily in Europe by a group of people from various companies and universities. However, two excellent American researchers also contributed substantially: Dr. Michael Senko and Dr. Bill Kent, both of IBM. Anyone reading this book will also enjoy reading the classics of Mike Senko published in the IBM Systems Journal and the pearl Data and Reality, the book written by Dr. Kent. In that period, NIAM was conceived. In the late seventies a group of international conceptual modelers undertook in ISO the task of writing the report Concepts and Terminology for the Conceptual Schema and the Information Base. It was a report about conceptual modeling, natural language, and logic.

In 1986, when I was professor of computer science at the University of Queensland, a relatively young Terry became my colleague as lecturer in the Computer Science Department. What a fantastic colleague! He very quickly caught on to my lecturing on conceptual modeling. It quickly became apparent to me that he was full of ideas, resulting in many collaborative sessions and the further development of the NIAM method at that time. His own lecture preparation was excellent, generating many exercises, and it was a real pleasure to work with him. We jointly published a book in 1989 which was largely written by Terry. In 1989, Terry completed a doctoral thesis that formalized and enhanced NIAM, and he and I went our own separate ways as I decided to return to The Netherlands.

In the following period, many excellent extensions to the NIAM 1989 version were added by Terry and his team on the one hand, and myself and associates on the other. In retrospect, I consider it a very good approach to work independently for some time and subsequently come to the conclusion that beautiful improvements have been developed. Two years ago, we decided to establish the best combination of the improvements developed independently. One of the strong points of our methodology is its incomparable ability to capture precise semantic intent and unambiguously express it graphically.

I strongly recommend every serious data modeler, business process modeler, and programmer to study this excellent book very carefully. I perused the chapters with pleasure and found it very useful and clearly presented. It is an excellent textbook for universities that intend to provide a first-class conceptual modeling course. UML has received much greater attention than ORM up till now, and I personally find that a shame, because in my opinion there are many areas in which ORM outperforms UML. I expect that this point will become clear to all with UML experience, who have their first encounter with ORM by reading this book. I therefore hope this book will result in further attention to ORM, which would be much deserved.

The relationship between the new OMG standard SBVR and ORM is not explicitly mentioned in the text, but be assured that there is a clear philosophical link between them. People familiar with both standards will recognize this easily.

Terry’s coauthor, Tony, has added a very interesting chapter about processes, and has incorporated the task of modeling these processes as part of conceptual modeling. Tony is an excellent teacher, as I have recently had the pleasure of witnessing at the ORM2007 Conference in Portugal: British humor thrown in for free!

It is my distinct pleasure to highly recommend this book to anybody seriously interested in acquiring competence in conceptual analysis or modeling, with the aim of making modeling an understandable form of engineering instead of considering it as just an art.