Analyzing Mappings and Properties in Data Warehouse Integration

The information inside the Data Warehouse (DW) is used to take strategic decisions inside the organization that is why data quality plays a crucial role in guaranteeing the correctness of the decisions. Data quality also becomes a major issue when integrating information from two or more heterogeneous DWs. In the present paper, we perform extensive analysis of a mapping-based DW integration methodology and of its properties. In particular, we will prove that the proposed methodology guarantees coherency, meanwhile in certain cases it is able to maintain soundness and consistency. Moreover, intra-schema homogeneity is discussed and analysed as a necessary condition for summarizability and for optimization by materializing views of dependent queries.