Chapter 2. Defining Logical Data Units
When describing a service in a WSDL contract complex data types are defined as logical units using XML Schema.
2.1. Introduction to Logical Data Units
When defining a service, the first thing you must consider is how the data used as parameters for the exposed operations is going to be represented. Unlike applications that are written in a programming language that uses fixed data structures, services must define their data in logical units that can be consumed by any number of applications. This involves two steps:
- Breaking the data into logical units that can be mapped into the data types used by the physical implementations of the service
- Combining the logical units into messages that are passed between endpoints to carry out the operations
This chapter discusses the first step. Chapter 3, Defining Logical Messages Used by a Service discusses the second step.