This is a much better way of learning to write XML schemas compared to formal language at the XML schema specification site.
Although there are some typos they do not glare the fine material in this book nor hinder learning.
Professional XML Schemas exhaustively details the W3C XML Schema language, and teaches the new syntax in an intuitive and logical way. From declaring elements and attributes, creating complex content models, and working with multiple namespaces, you'll move on to see how XML Schemas are used in real-world situations. A number of practical case studies will illustrate the design and creation of schemas in the diverse worlds of relational databases, document management, and e-commerce applications.
This book covers: A complete guide to XML Schema Syntax Using XML Schema built-in types, and deriving new types Working with XML Schemas and namespaces Creating identity and uniqueness constraints Good XML Schema design, illustrated in a number of different areas Working with XML Schemas and XSLT Writing XML Schemas for working with SOAP Integrating Schematron and XML Schemas