43. The method of claim 42 further comprising generating a database view of the plurality of inter-related data sources, using the federated schema, wherein the database view is formulated in terms an expression language that uses the classes, the properties, the inheritances, and the business rules, and wherein generating the query comprises generating the query for the data base view.
43. The method of claim 42 further comprising generating a database view of the plurality of inter-related data sources, using the federated schema, wherein the database view is formulated in terms an expression language that uses the classes, the properties, the inheritances, and the business rules, and wherein generating the query comprises generating the query for the data base view. 44. The method of claim 43 wherein generating the database view comprises automatically embedding the business rules within view definitions.