Weak functional dependencies on trees with restructuring

We present an axiomatisation for weak functional dependencies, i.e. disjunctions of functional dependencies, in the presence of several constructors for complex values. The investigated constructors capture records, sets, multisets, lists, disjoint union and optionality, i.e. the complex values are indeed trees. The constructors cover the gist of all complex value data models including object oriented databases and XML. Functional and weak functional dependencies are expressed on a lattice of subattributes, which even carries the structure of a Brouwer algebra as long as the union-constructor is absent. Its presence, however, complicates all results and proofs significantly. The reason for this is that the union-constructor causes non-trivial restructuring rules to hold. In particular, if either the set- or the the union-constructor is absent, a subset of the rules is complete for the implication of ordinary functional dependencies, while in the general case no finite axiomatisation for functional dependencies exists

Modellgetriebene Entwicklung inhaltsbasierter Bildretrieval-Systeme auf der Basis von objektrelationalen Datenbank-Management-Systeme

In this thesis, the model-driven software development paradigm is employed in order to support the development of Content-based Image Retrieval Systems (CBIRS) for different application domains. Modeling techniques, based on an adaptable conceptual framework model, are proposed for deriving the components of a concrete CBIRS. Transformation techniques are defined to automatically implement the derived application specific models in an object-relational database management system. A set of criteria assuring the quality of the transformation are derived from the theory for preserving information capacity applied in database design.In dieser Dissertation wird das Paradigma des modellgetriebenen Softwareentwurfs für die Erstellung von inhaltsbasierten Bildretrieval-Systemen verwendet. Ein adaptierbares Frameworkmodell wird für die Ableitung des Modells eines konkreten Bildretrieval-Systems eingesetzt. Transformationstechniken für die automatische Generierung von Implementierungen in Objektorientierten Datenbank-Management-Systemen aus dem konzeptuellen Modell werden erarbeitet. Die aus der Theorie des Datenbankentwurfs bekannten Anforderungen zur Kapazitätserhaltung der Transformation werden verwendet, um Kriterien für die erforderliche Qualität der Transformation zu definieren