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Reviewer: Daniel J. Schuster

The use of object-oriented principles to create database applications is presented in this book. According to the authors, object-oriented modeling techniques have helped lower the cost of database applications, shorten their time to market, improve their quality, and increase customer satisfaction. I would add that implementation tools that support these techniques, such as Sybase's PowerBuilder and SQL Anywhere, are required in order to see major gains. This book is intended as a sequel to Rumbaugh et al. [1]. It focuses on database applications and is intended for practitioners. It contains a remarkable amount of information for people who are creating business systems. The book starts by defining object modeling technology (OMT). OMT uses three models. The object model is used to represent the static structure. The functional model defines the necessary computation and processing. Finally, the dynamic model shows the time-dependent interactions, which are critical in such areas as industrial process control, but are seldom important in database applications. Next, an analysis and design process is defined and illustrated with an example. The authors advocate creating an object model and then building the functional and dynamic models as needed, instead of starting with dataflow diagrams. The step-by-step development of software for managing investment portfolios using OMT is well done and easy to follow. The authors' recommendation to partition large models into more easily grasped smaller packages is sound. Decision tables can be elegant in situations where various otherwise confusing combinations of conditions must lead to different procedures. The authors encourage their use. The authors show how to implement applications from the models using three different approaches: file, relational database, or object-oriented database. Program code for a prototype implementation using MS-Access has been put in the public domain and is available on the Internet. The discussion of the advantages and disadvantages of using MS-Access 2.0 provides excellent insight into the database software issues. The authors recommend using computer-aided software design tools, which are now powerful and easy to use. A discussion of the key features of products such as PowerDesigner and System Architect would be a good addition to the book. Finally, the authors discuss large system issues: distributed databases, integration of systems of applications, and reverse engineering of legacy databases. The authors use the Unified Modeling Language of Booch, Rumbaugh, and Jacobson for their object model. They include a Backus-Naur form grammar for the public-domain Object Navigation Notation. The Object Model Notation for the functional model has also been placed in the public domain to encourage its use. The book is well organized, with chapter introductions and summaries, bibliographic notes, and references for most chapters. A glossary defines approximately 200 terms. The book is designed to be used as a textbook. Exercises are included, and solutions are available from the publisher.