Using XML with Legacy Business Applications

Complex Content Elements

In this section we discuss Elements that may have child Elements, that is, those with complex content models. Although it may seem counterintuitive, in some ways these are easier to understand than the simple content Elements discussed in the previous section. One of the reasons for this is that while many features for defining simple content Elements and types are commonly used, relatively few of the features for defining complex content Elements are seen in the wild.

Complex types are specified in Part 1: Structures of the Schema Recommendation. It is, of course, the final source and arbiter of any of these concepts. However, Part 1 is so littered with constraints and validation rules that finding the basic definitions ...