There are various fundamental stages of Data warehousing. They are:
1. Offline Operational Databases: This is the first stage in which data warehouses are developed simply by copying operational system database to an offline server were dealing out a load of reporting not put any impact on the performance of the operational system.
2. Offline Data Warehouse: In this stage of development, data warehouses are updated on a regular basis from the operational systems. Plus, all the data is stored in an incorporated reporting-oriented data structure.
3. Real-Time Data Warehouse: During this stage, data warehouses are updated on an event or transaction basis. Also, an operational system executes a transaction every time.
4. Integrated Data Warehouse: This is the last stage where data warehouses are used for generating transactions or activity passing back into the operating system for the purpose of use in an organization's daily activity.
