Bücher von Karl Wiggisser

Information systems, which oftentimes are in charge of supporting decision finding processes in companies and public administration, model the real world. But the world is changing and in such a setting information systems can only cope with their tasks, if they can be kept consistent with the real world. For that purpose they have to be able to deal with modifications in the data schema ¿ representing environmental changes ¿ and their influence on the data values, to ensure correct and reasonable query results. Based on the COMET Metamodel for Temporal Data Warehouses, this thesis addresses three substantial aspects of change management for data warehouses: (1) Management of Structure Versions, (2) Identification of Changes between versions, and (3) Transformation of cell data.