Data integration is an important topic for serviceoriented architecture (SOA) because it is so often neglected. However, in SOA the data and information are as valuable, if not more valuable, than the services or processes that sit on top of the information. In fact, as people implement SOAs, most of the services they are setting up are data services. Data services can be viewed as the foundation of SOA. If data services are not set up correctly, the chances of having successful SOA are reduced.

This document addresses these topics:

• Goals and characteristics of SOA
• The SOA Meta model, with a detailed discussion of the data abstraction and data services layers
• Practical implementation advice, specifically about Service Data Objects (SDO) and XQuery