Case Method, Entity Relationship Modelling (Computer Aided Systems Engineering) - Softcover

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The purpose of this book is to provide data analysts, strategists and data administrators with a definitive guide to Entity Relationship Modelling. At the same time, I was very keen that the book should be well-thumbed by regular use, as opposed to sitting on someone's shelf.

I believe that a sound grasp of entity relationship modelling can provide a firm architectural framework for understanding a business and creating flexible systems for the future. There are, however, many things that need to be considered over a period of time to take advantage of these basic techniques.

Not least of these considerations is understanding the meaning of words as applied by our users and separately within the Information Systems department. It is certainly my experience that many system developments fail because of the use of jargon and protectionism within the ivory tower of the Information Systems department, coupled with the bewildering explosion of technology. In this book I am implicitly recommending that analysts must discard their egos, and instead recognize that there is strength in their Human fallibility. In practical terms it means seeking out the most thorough and accurate understanding of the business, and then exposing that to your users and peers so they can help you gain even more accuracy. I have seen this 'egoless' team approach not only enable teams to build far more appropriate systems but act as a catalyst, knitting together users, system development staff and even accountants.

How to Use This Book

I hope this book will be used by novice and expert alike. It has, therefore, been designed to provide easy-reading, tutorial-like chapters and definitive reference chapters and appendices. Later chapters contain more complex examples and techniques to be used once you have mastered the basic techniques. A single example runs through the book, based on a hypothetical airline. However, other examples and common problems are provided to help minimize your learning curve.

The appendices are designed to cover other useful concepts, further detail quality checks, first-cut database design and data administration. All the important terms in the book are covered by the glossary and, finally, an extensive index and the contents list are there to provide alternative entry points to the information in the book.

This book should provide 'hot-line' support to your entity relationship modelling when that really key problem requires urgent resolution.

Acknowledgments

Writing a book about something you have been doing for years sounds straightforward. I found myself going over projects and discussions from the last twenty years. It is really amazing what I have learnt from my colleagues in England and the United States, and especially from many of the users who kept insisting that we really must cater for yet another important exception.

Ensuring that the book itself is complete, consistent and coherent was a tedious but worthwhile task. I would like to thank my close colleagues who took the time to expose ambiguities, difficulty in understanding, errors and omissions. In particular I would like to say a special thank you to Barbara, my wife, with whom I have worked weekends and into the early hours whilst we struggled with definitions, style, diagrams and terminology.

Richard Barker
July, 1989