Book excerpt: This book touches on an area seldom explored: the mathematical underpinnings of the relational database. The topic is important, but far too often ignored. This is the first book to explain the underlying math in a way that’s accessible to database professionals. Just as importantly, if not more so, this book goes beyond the abstract by showing readers how to apply that math in ways that will make them more productive in their jobs. What’s in this book will "open the eyes" of most readers to the great power, elegance, and simplicity inherent in relational database technology.