"Extending data warehouses with reasoning over multi-dimensional ontologies: a proof-of-concept prototype using PL/SQL and OWL"
, in Masterarbeit am Institut für Wirtschaftsinformatik - Data & Knowledge Engineering, Betreuung: o. Univ.-Prof. Dr. Michael Schrefl, unter Anleitung von Dr. Bernd Neumayr: Masterarbeit, 9-2014
Extending data warehouses with reasoning over multi-dimensional ontologies: a proof-of-concept prototype using PL/SQL and OWL
Sprache des Titels:
In this thesis a prototype for the reasoning over multi-dimensional ontologies (MDO) is presented. The contribution of this thesis is to proof the feasibility of the introduced ideas by providing a research prototype that can be extended in the future. With the help of multi-dimensional ontologies an OLAP cube can be enriched with business terms, also called concepts. These concepts are in an unordered state when defined in the MDO. Reasoning support over multi-dimensional ontologies simplifies the use of these concepts by arranging them in hierarchies. An abstract syntax is defined in UML and implemented in a database schema, the MDO DB, this syntax represents the abstract MDO language. To ease the task of working with this prototype also a concrete syntax is implemented in ANTLR to interact with the prototype without knowing its inner behavior, this ANTLR implementation represents the concrete MDO language. The prototype shows the mapping of concepts from their MDO definition to OWL, with the concepts defined in OWL. A reasoner is used to create the subsumption hierarchy of the concepts. The thesis also provides a mapping from MDO to SQL views. With these views a standard data warehouse is enriched with business terms and these terms can be used in further queries. The prototype itself is also part of the Semantic Cockpit research project and implements main parts of it.