Automatic schema merging using mapping constraints among incomplete sources

Schema merging is the process of consolidating multiple schemas into a unified view. The task becomes particularly challenging when the schemas are highly heterogeneous and autonomous. Classical data integration systems rely on a mediated schema created by human experts through an intensive design process. In this paper, we present a novel approach for merging multiple relational data sources related by a collection of mapping constraints in the form of P2P style tuple-generating dependencies (tgds). In the scenario of data integration, we opt for minimal mediated schemas that are complete regarding certain answers of conjunctive queries. Under Open World Assumption (OWA), we characterize the semantics of schema merging by properties of the output mapping system between the source schemas and the mediated schema. We propose a merging algorithm following a redundancy reduction paradigm and prove that the output satisfies the desired logical properties. Recognizing the fact that multipl...

• Type: Journal
• Year: 2010
• Where: CIKM
• Authors: Xiang Li 0002, Christoph Quix, David Kensche, Sandra Geisler
• Keywords: CIKM 2010, Data Integration, Database Management, Information Technology, Mediated Schemas