Bernhard Thalheim, Christian-Albrechts-University at Kiel Germany.
Prof. Dr.rer.nat.habil. Bernhard Thalheim (Director, Department of Computer Science, Faculty of Engineering at Christian-Albrechts University Kiel, Germany) (MSc, PhD, DSc) is full professor at Christian Albrechts University in Germany. His major research interests are database theory, logic in databases, and systems development methodologies, in particular for web information systems. He has published more than 300 refereed publications, edited more than 30 conference volumes, co-founded three international conferences, and has been programme committee chair for almost three dozen international conferences such as MFDBS, ER, FoIKS, ASM, SDKB, NLDB and ADBIS. He got several international awards, e.g. the Kolmogorov professorship at Lomonossow University Moscov and the P.P. Chen award of Elsevier. He has been an associated professor at Dresden University of Technology, a visiting professor at Kuwait University, Alpen-Adria University Klagenfurt and others, and a full professor at Rostock University and Brandenburg University of Technology at Cottbus.
The theory of database constraints has been developed for a long time within the relational database modelling setting. The 80ies brought a large body of knowledge and led to the impression that the theory development is completed. A typical example is normalisation theory that has been developed inside the relational understanding. It must already reconsidered for the table database modelling setting. Cardinality constraints defined in an entity-relationship modelling setting were the most essential addition to the theory of relational constraints. It seems that the theory of object-relational constraints is still a lacuna. Therefore, monographs and textbooks remain to be on the level of the early 90ies as far as constraints are considered. Database technology brought however powerful and sophisticated systems. So, the constraints that might be supported without loss of performance are far richer. Database applications need more sophisticated constraints. So, the paper presents some solutions for constraint enhancement, constraint handling, structure optimisation, and database modelling at the conceptual level. It completes with open problems.