Types of Data Warehousing

Off line Data Warehouse

Data warehouses at this stage are updated from data in the operational systems on a regular basis and the data warehouse data is stored in a data structure designed to facilitate reporting. 

Real Time Data Warehouse 

Data warehouses at this stage are updated every time an operational system performs a transaction (e.g. an order or a delivery or a booking.) 

Integrated Data Warehouse

Data warehouses at this stage are updated every time an operational system performs a transaction. The data warehouses then generate transactions that are passed back into the operational systems.