An Architecture for Federated Database Metadata
نویسندگان
چکیده
One of the eeorts of the LIOM group has been the construction of a federated database architecture which facilitates a dynamic healthcare environment. Changes occur in a federated database environment when attributes are added, removed or modiied at local database level, or when an entire node (database) is added or removed. Database systems use a powerful construct called metadata to deene the stored information and services. In federated database systems, metadata generally means the virtual schemas which reside above the local schema in the federated architecture. In this paper we discuss our use of metadata to provide a dynamic architecture for federated database systems.
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