It's one thing to integrate data across applications in an IT infrastructure. The methods and practices are tried and true. But implementing data integration across a service-oriented architecture poses new challenges."SOA starts to blur the difference between data and applications," says Ron Schmelzer of ZapThink, an SOA market research firm. When a set of applications performs some function, isolated as an independent service, the results can look a lot like data as they're passed off to another application. Likewise, a query to a service that triggers a stored procedure in the database yields results that look a lot like an outcome of application logic. In services, data ceases to exist as something distinct from the application logic.
