Data warehouses differ significantly from traditional transaction-oriented operational database applications. Indexing techniques and index structures applied in the transaction-oriented context are not feasible for data warehouses. This work develops specific heuristic indexing techniques which process range queries on aggregated data more efficiently than those traditionally used in transaction-oriented systems. The book presents chapters on: the state of the art in data warehouse research data storage and index structures finding optimal treebased index structures aggregated data in treebased index structures performance models for treebased index structures and techniques for comparing index structures.