Mapping OWL ontologies to relational schemas

Many applications require storing XML data, which can be achieved by using a relational database (RDB). In order to accomplish that, we need a set of transformation rules that maps the XML structure to a collection of relations. However, XML files from the same application domain might have different structures, making the mapping process to a unique relational schema more difficult. To overcome this, we can previously generate an integrated schema that represents the individual XML structures, and then map it to the relational format. Afterwards, the original XML files are stored into the database. In our proposal, the integrated schema is represented as an ontology. In this paper, we propose a mechanism for generating the relational schema from a set of integrated XML files, which includes defining a set of mapping rules from the OWL (Ontology Web Language) ontology to the relational format. The mapping process is implemented in OntoRel tool.