Phil Windley on Virtual Databases:
A virtual database, or federated database, provides a single, virtual interface to a collection of data sources. These data sources may live in multiple databases from multiple vendors and even be in multiple formats (relational vs hierarchical for example). To make this work, the organization deploying the virtual database creates a data model that contains the needed elements of each of the data sources being integrated and then creates a map from the existing data sources to the new data model. Using this model and map, the virtual database management system processes queries, updates, insertions, and deletions of the integrated data.
I think that data integration is the key to the integration puzzle, whether you're going to use Web services, EII, or EAI. I think we've actually never realized the chief benefit of databases. A database is commonly thought of my lay people as vast collections of valuable data. But we know better. For the most part, we use it as just a persistent portion of the program's variables.
And, yes, this is the year of integrating applications at work. Windley is pointing out a middle-weight virtual database, or Enterprise Information Integration, sitting between web services and full-scale Enterprise Application Integration.
As I understand it the virtual database holds the references to all the other databases and points applications to the right place for data they are accessing. It works as a model of the data available and a roadmap to the data, but does not contain data. The idea of a universal model pulling from all the various databases might well be a solution, although I'll have to map some of this out to see how it might fit our needs. Not yet sure.
Posted at June 18, 2003 01:10 PM | TrackBack