ontological data dependencies
relational data models
The paper provides brief analysis of the state of the art in the area of “ontology based” data access systems and of the possible influence of such works on the development of research in the database and information systems fields. The issues of correlation between ontological and conceptual modeling and between the respective languages are discussed. An analysis of development of the languages based on description logics and oriented on their use as a facility for conceptual modeling in the database context is given in brief. Short overview of experimental results of development of “ontology based” data access systems is also provided.
Elaboration of description logics intended for application in the context of databases and information systems as well as creation of “ontology based” data access systems show that development of the DL-Lite description logics family providing an efficiency acceptable for the work with databases is an important result. Description logic languages and the respective conceptual models can be mapped into the existing data models of the database integration systems preserving their semantics. Research and development performed in the area of description logics are important for inclusion of the relational databases into the Semantic Web context.
An alternative approach for efficient support of queries over database schemas with ontological dependencies being developed by Georg Gottlob and his colleagues in accordance with the database technology trends looks very promising. They have defined the Datalog± language family being more expressible than the logics of the DL-Lite family. Overview of the
Datalog± languages is planned to be provided in another paper.