The Data Warehouse
Twelve Rules That Define a Data Warehouse
1. The Data Warehouse and operational environments are separated.
2. The Data Warehouse data are integrated.
3. The Data Warehouse contains historical data over a long time horizon.
4. The Data Warehouse data are snapshot data captured at a given point in time.
5. The Data Warehouse data are subject-oriented.
6. The Data Warehouse data are mainly read-only with periodic batch updates from operational data. No online updates are allowed.
7. The Data Warehouse development life cycle differs from classical systems development. The Data Warehouse development is data driven; the classical approach is process driven.