THE DATA ADMINISTRATION NEWSLETTER – TDAN.com
ROBERT S. SEINER – PUBLISHER

Author: Barbara von Halle
Publisher: Wiley and Sons, 2002
ISBN 0471412937 

When I received a copy of Business Rules Applied, my first thoughts were, "wow, 500 plus pages of the latest leading-edge thinking on business rules". Well, time for expectation setting: this book is most definitely not 500-plus pages about leading-edge business rules thinking. In fact, only two of the five sections in the book are only about business rules per se. The other sections cover a wide range of topics, including data modeling, facilitated requirements gathering, application-development methodology, project management, and commercial software products.

To the point, the reader should take seriously the term "applied" in the title, as well as the subtitle. This monumental, pivotal work is not only about business rules, but is also about how to put business rules to work while doing the job of creating computer applications for business. The scope of the book leaves no doubt that the author is a seasoned practitioner who has actually been there and done it--not only building business applications, but applying business rules while doing so, as well.

The first two chapters do comprise a comprehensive overview of current thought by industry leaders, including Ronald Ross and Chris Date, on business rules--what they are, how they are classified, how they are connected with the relational model of data. The ”applied" part of the book consists of the remaining chapters 3 through 15.

The primary technique by which von Halle recommends applying business rules to application development is by adding a "rule track" to the conventional data, process and technology tracks. Skeptical project managers may groan at the heaping-on of what may appear at first to be incremental work effort. But the addition of a rules track to a project does not result in more work, but rather re-allocates work which would have been addressed--probably much less rigorously--in the data or process tracks. So the net amount of work should ideally decrease, due to less redundancy of effort, less rework, smoother transitions between phases, as well as result in a higher-quality and more reusable end product.

Readers familiar with von Halle's earlier landmark Handbook of Relational Database Design (if you're not, shame on you) will recognize the step-by-step, outline-numbered breakdown of the project workflow, from analysis through implementation and management of the implemented rules facilities.

Some additional highlights to be found within Business Rules Applied:

• Coverage of "rule templates" and "rule clauses", the formal patterns by which business rules should be expressed
• Integration of rules techniques with data analysis and database design, resulting in a "rule-enriched logical data model"--one would expect nothing less from a pioneer in the relational database field
• Rule analysis techniques: "rules for rules", the rigorous application of which will transform a set of discovered rules into a logical rule model
• Distinguishing characteristics of "data-change-oriented" versus "service-oriented" commercial rules products

The shortcomings of the book are few. The author bends over backwards to accommodate object orientation, with qualified success. On the other hand, von Halle neglects any mention of Object Constraint Language (OCL), the subset of Unified Modeling Language (UML) proposed for modeling of business rules. OCL has been criticized as being severely limited in expressing and implementing a robust rules capability, and Chris Date has written extensively on this subject. But if for no other reason than its visibility as part of the ubiquitous UML standard, OCL warrants some coverage within such a comprehensive business rules publication.

The index is excellent--very extensive and well organized. (For what it's worth: a good index in a technical book is an indispensable tool for the reader, a joy to find, and excruciatingly painful, non-gratifying, and tedious to create.)

In short, this book definitely meets expectations. Business rules are the most significant area of advancement within IT thought leadership today, and anyone who wishes to keep up with business rules--and their application--should not be without a copy of Business Rules Applied.