Since a data warehouse is a historical copy of data, the storage requirements will increase over time. In the case of an upgrade of the source system, the data warehouse may need to be updated accordingly.
Some application vendors provide a corresponding integrated data warehouse, but this is not typical. Most data warehouse systems are custom-built.
Advantages of data warehouses are as follows:
- Integrate data from heterogenous sources
- Perform historical analysis over large amounts of data without impacting operational systems
- Enable cross-functional analysis
- Improved data quality
- Converge disparate systems to a common semantic
Disadvantages of data warehouses are as follows:
- Usually require ...