Abstract. The general topics of the data integration problem are discussed, including ontology-oriented data integration in the semantic web. The importance of establishing mappings between ontologies and relational databases is indicated, and a brief analytical review of researches on this topic is given. The binary relational data model is defined and the mapping of the ALC description logic and its extensions to the binary relational data model is described.

Keywords: data integration, ontology, semantic web, description logic, binary relational data model.