The range of topics presented here helps make this title a success. While there is some leading-edge (and somewhat obscure) material on emerging topics in XML Schemas, much of the book avoids XML "language lawyering" and concentrates on delivering a solid tour of the basics. The authors walk before they run, taking the reader along with basic XML Schema constructs to define simple data types in XML. They show off elements, attributes, and simple data types. (There's coverage of the full complement of over two dozen built-in XML Schema data types for numerical, string, date, and IDREFs.) The earlier sections include the author's own sample classes for a handful of common data types for such common entities as people's names, countries, IP addresses and URIs, plus geographical locations. Fully internationalized, these samples can serve as a basis for entities in your custom projects.

The second half of the book digs into design strategies at a higher level, dealing more with XML Schemas. The authors cover several reusable design strategies for creating workable XML Schemas (like the Russian Doll, the Slice, and finally the Venetian Blind model, which blends the first two). There's discussion of the best ways to express required and optional elements, along with choice values and ordering of required elements. Integration with XML namespaces and a discussion of the issues surrounding reuse in XML Schemas (like combining and extending existing datatypes) show how powerful this standard really is.

Valuable chapters on using XML Schemas with databases (including expressing relational integrity and normalization), plus the differences between XML Schemas used for document management will help you make the right design choices in each setting. The book closes with a discussion and tour of late-breaking tools like Schematron (and its competitors) as well as the possibilities for functional programming with XML Schema in schema-based programming (SBP).