developerWorks has just published the paper, on the Preferred Data Source Pattern, a Service-Oriented Architecture (SOA) pattern that allows a client to retrieve information from a set of information sources, without knowing (at least at a high level) that multiple sources exist.
The Preferred Data Source Pattern, or Preferred Source Pattern, is a microflow pattern for service aggregation. The pattern allows a client to retrieve information from a group of information sources without the need to understand, at least at a high level, that multiple sources exist.
Consider the following situations where multiple data sources must appear as one:
- A company has multiple sources of information, some of which are more expensive to access than others (for example, a local parts database and a remote parts database).
- A company upgrades its IT systems and, in doing so, introduces new sources of information that it must use in conjunction with old sources (for example, customers).
- One or more similar businesses merge, and all have somewhat dissimilar data representing the same entities, such as customers.
- Any individual entity has some enterprise-unique identifier that's part of the record (for example, a customer number or SKU).
You can find the paper here: http://www-128.ibm.com/developerworks/webservices/library/ws-patterns/index.html