Modeling and executing the data warehouse refreshment process

Data warehouse refreshment is often viewed as a problem of maintaining materialized views over operational sources. In this paper, we show that the data warehouse refreshment process is a complex process comprising several tasks, e.g., monitoring, extracting, transforming, integrating and cleaning operational data, deriving new data, building histories and loading the data warehouse. We propose a novel approach for defining and executing the refreshment process based on specifications stored in an object-oriented metadata repository. Our approach considers the multidimensional character of OLAP data and can be used in conjunction with various operational sources and target data warehouses