Ontologies are one of the key technologies for data integration and meta-databases, by connecting databases on a semantical level. Still, everything fails when one of the database schemas changes: specific parts of the ontology have to be reconstructed by hand. We propose an approach that allows the database schema and the ontology to change and evolve, without ever losing their connection to each other. We call that "coevolution". Coevolution cannot be completely automated, as data definition languages do not define the change of semantical concepts, but only technical schema changes. In this paper we present our mapping of database schemas to ontologies, describe how these ontologies can be enriched by semantical information and show our approach to transfer schema changes to the ontology