The Knowledge Quality Management Team

Data warehouses are basically organized two dimensionally, reflecting time and granularity. Data loaded from operational systems are regarded as current data that 

Incoming data from operational systems as well as those from external sources, collectively referred to as source systems, are stored in a data staging area. Several modules support the sorting, categorization, transformation, combination, and dereplication of data stored in the staging area to prepare them for use in the data warehouse. The data staging area does not provide any query or visual representation of data. 

The presentation server provides the query capabilities and the visualization of data to the end-users and to other applications. 

The entire process of data transition from the source systems to presentation servers via the data staging area is usually referred to as extract, transform, and load (ETL). 

Data warehouses provide the following generic data storage areas  

---