Local Schemas Modifications Propagation and Maintenance of Metadata in Multidatabase System

One of the challenging problems in the multidatabase systems is to find the most viable solution to the problem of interoperability of distributed heterogeneous autonomous local component databases. This has resulted in the creation of a global schema over set of local component database schemas to provide a uniform representation of local schemas. The main objective of this paper is to maintain the Global Schema and the Global Directory/Dictionary/Metadata as the local schemas are autonomous and evolve over time. In this paper we consider uniform object-oriented data models which is used during integration of different heterogeneous distributed databases from different data models and proposed a framework to maintain an objected-oriented Global Schema in the multidatabase system. The Bottom up local schema modifications propagation in the Global schema is proposed and during this process the Global Directory/Dictionary/Metadata is maintained without manual intervention.