Towards a Comprehensive Methodological Framework for Semantic Integration of Heterogeneous Data Sources

Nowadays, data can be represented and stored by using different formats ranging from non structured data, typical of file systems, to semistructured data, typical of Web sources, to highly structured data, typical of relational database systems. Therefore, the necessity arises to define new models and approaches for uniformly handling datasources having different formats and structures, and obtaining a global, integrated, and uniform representation. In this paper we present three approaches to data integration and propose a unifying framework integrating the various methodologies and incorporating techniques developed separately. We also present the architecture of a metadata repository supporting the integration framework.