Integration mapping rules: Transforming relational database to semantic web ontology

Semantic integration became an attractive area of research in several disciplines, such as information integration, d atabases and ontologies. Huge amount of data is still stored in relati onal databases (RDBs) that can be used to build ontology, and the atabase cannot be used directly by the semantic web. Therefore, one o f th main challenges of the semantic web is mapping relation l databases to ontologies (RDF(S)-OWL). Moreover, the use of manual wor k in the mapping of web contents to ontologies is impractical because it contains billions of pages and the most of these contents a re generated from relational databases. Hence, we propose a new pproach, which enables semantic web applications to access relation al databases and their contents by semantic methods. Domain ontologies can be used to formulate relational database schema and data in order to simplify the mapping (transformation) of the und erlying data sources. Our method consists of two main phases: building on tology from an RDB schema and the generation of ontology inst ances from an RDB data automatically. In the first phase, we studied fferent cases of RDB schema to be mapped into ontology repr es nted in RDF(S)-OWL, while in the second phase, the mapping rules a r used to transform RDB data to ontological instances repre s nt d in RDF triples. Our approach is demonstrated with examples, va lidated by ontology validator and implemented using Apache Jena in Java Language and MYSQL. This approach is effective for building ontology and important for mining semantic information fro m huge web resources.