Data Integration in the Large: The Challenge of Reuse

Much published research on data integration considers only a “one shot” effort to produce an integrated schema or a multidatabase query. This paper examines a more complex environment. Our clients CBST~ out multiple integration efforts, producing multiple kinds of integrated systems that involve overlapping subsets of their component databases. Metadata is costly to collect and maintain, so one wishes to reuse it wherever possible. We thus must devise ways to reuse integration metadata across integration efforts, though the efforts may have different goals and may concern overlapping subsets of the components. This paper identifies and examines issues of maximing information and code reuse by organizations facing data integration in the large.