Description: In the beginning of data warehouse, a data warehouse was given a simple definition. That definition was (and still is today):
Data warehouse —
+ subject oriented
+ time variant
+ nonvolatile collection of data for management’s decisions.
In addition, we have come to learn that data warehouses are granular. They contain the bedrock data that forms the single source for all DSS processing. With a data warehouse there is reconcilability of information when there are differences of opinion. And the atomic data found in the warehouse can be shaped in many ways, satisfying both known requirements and standing ready to satisfy unknown requirements.