RWTH Aachen University
Peer data sharing systems use either schema-level or data-level mappings to resolve schema as well as data heterogeneity among data sources (peers). Schema-level mappings create structural relationships among different schemas. On the other hand, data-level mappings associate data values in two different sources. These two kinds of mappings are complementary to each other. However, existing peer database systems have been based solely on either one of these mappings. The authors believe that if both mappings are addressed simultaneously in a single framework, the resulting approach will enhance data sharing in a way such that they can overcome the limitations of the non-combined approaches.