Inconsistency checking and resolving of CWM metadata based on Description Logics

The inconsistencies in metadata have remarkable influence on the stability and reliability of data warehouse system. During the metadata creation based on Common Warehouse Metamodel(CWM), the different experiences and views of describing data of organizations involved in metadata creation bring metadata on inconsistencies inevitably. However, detecting and resolving these inconsistencies in CWM metadata automatically is difficult because CWM metamodel and metadata are rendered to users by graphs, which lack precise semantics. In this paper, we research how to check and resolve CWM metadata inconsistencies in terms of a logic belonging to Description Logics. First, we make a study of how to formalize CWM metamodel and metadata by means of the presented Description Logic DL_id which supports identification constraints on concept. Then we research how to check metadata inconsistencies by query and reasoning mechanism of DL_id. At last, we propose the approach for resolving inconsistencies through defining inconsistency resolution rules in DL_id knowledge base. The results of the experiments with reasoning engine RACER are encouraging.