Object-Oriented Modeling of Meta Information for Semantic Schema Enrichment and (Semi-)Automatic Schema Transformation

In this paper, we describe a framework for an object-oriented modeling of meta information. The meta information consists of all kind of information necessary to access and interoperate the participating databases. As part of the meta information, we model the common properties and differences of the various data models and concrete systems. We also include information to semantically enhance the schemas of the participating databases and provide the basis for an automatization of the schema transformation process. We describe possibilities to (semi-)automatically transform flat relational schemas into structured object-oriented ones which are more adequate to model complex real world problems. We use the object-oriented data model as target model of the transformation because of its semantic richness and its availability as commercial systems. The meta information necessary for the schema transformation may be user supplied or it may be deduced from an entity-relationship design schema and corresponding mapping information.