Features of a Warehouse:

•It is separate from Operational Database.
•Integrates data from heterogeneous systems.
•Stores HUGE amount of data, more historical than current data.
•Does not require data to be highly accurate.
•Queries are generally complex.
•Goal is to execute statistical queries and provide results whichcan influence decision making in favor of the Enterprise.
•These systems are thus called Online Analytical Processing Systems (OLAP).