1. The term “OLAP” is variously understood by software producers. Some associate it directly with the physical organization of data in a data warehouse, whereas others refer to it as tools that are designed for business reporting. Those tools are integrated into the data warehouse, sometimes even directly into the source systems, and have their own built-in data storage mechanisms. In this book, this term is used in reference to tools devised for business reporting and analysis, which are integrated with the properly designed and optimized data warehouse.
2. Codd, Codd, and Salley (1993).
4. This book does not discuss the implementation of star schema in various data models, which are called ROLAP, ...