Organizations generally start off with relatively simple use of data warehousing. Over time, more sophisticated use of data warehousing evolves. The following general stages of use of the data warehouse can be distinguished:
Data warehouses in this initial stage are developed by simply copying the data of an operational system to another server where the processing load of reporting against the copied data does not impact the operational system’s performance.
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.
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.)
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.