Mapping relational database for Semantic Web

Though efforts to build up a Semantic Web, where each machine can understand and interpret the data it processes, a vast amount of information resources is usually still stored in ordinary relational databases. So an effort has to be made in the direction of mapping these relational databases in a form that may be machine readable and making the semantics as expressed more explicit by relational databases. This paper presents an approach for mapping relational databases in Resource Description Framework (RDF) language. The proposed approach uses RDF Schema as mechanism to perform mapping relational databases to predefined domain ontology (or mediated ontology). Given a set of these mappings, the answering query through a mediated ontology is reformulated SQL query over underlying relational databases.