In order to solve the problem of multiple relational databases in different disciplines of a business (accounting, marketing, production, etc.), a database warehouse is a large, integrated source of data. A database warehouse occupies a lot of data, (usually in the terabytes or petabytes) and is an informational database.
Properties
- Is an informational database:
- Subject oriented:
- Organised over certain subjects, e.g. sales, customers, products, and more.
- Data stored is validated and integrated
- Data from different systems converted to a common format.
- Data from various sources validated before being stored in database warehouse.
- Time variant:
- Include the timestamps when data was collected, updated by a schedule.
- Can be used to provide historical data analysis
- Non-volatile:
- Normal users only have read access.
- All updates is done by an ETL (Extract, Transform, Load) process, started by a database administrator.
