Bill Inmon, one of the pioneers of data warehouses for business, defined a warehouse "a subject-oriented, integrated, time variant, and non-volatile collection of data used in strategic decision making. This text brings together Inmon's relational modeling approach to warehouses with other design philosophies more reliant on dimensional modeling. The authors describe types of data models used for different "business intelligence" functions, explore the step-by-step construction of a data warehouse model, and discuss deployment issues and common problems"