Managing Global Constraints in Multidatabase Syatems

Abstract

Various issues in multidatabase systems were studied, incleding resolution of intereoperability problems, database integration, query processing, and transaction management. However, deriving global constraints from the individual local constraints is rarely considered.Global constraints in multidatabase systems may be used to (a)avoid local constraint checking,(b) accomplish semanlic query optimization, (c)resolve interoperability problems,and(d)specily semantic relationships among databases. In this paper, we analyze the types of local consyraints and the ways of global schema construction to come up with a set of rules for global constraint derivation. The enforcement of the global constraints considering various types of update operations is also presented.