Authors:
Valéria Pequeno
1
and
Helena Galhardas
2
Affiliations:
1
INESC-ID, Portugal
;
2
Instituto Superior Técnico and INESC-ID, Portugal
Keyword(s):
Schema Matching, Correspondence Assertions, Data Integration, Relational Model.
Related
Ontology
Subjects/Areas/Topics:
Coupling and Integrating Heterogeneous Data Sources
;
Databases and Information Systems Integration
;
Enterprise Information Systems
Abstract:
When dealing with the data integration problem, the designer usually encounters incompatible data models characterized by differences in structure and semantics, even in the context of the same organization. In this work, we propose a declarative and formal approach to specify 1-to-1, 1-m, and m-to-n correspondences between relational schema components. Differently from usual correspondences, our Correspondence Asser- tions (CAs) have semantics and can deal with joins, outer-joins, and data-metadata relationships. Finally, we demonstrate how we can generate mapping expressions in the form of SQL queries from CAs.