Benefits of a data warehouse

• Maintain data history, even if the source transaction systems do not.
• Integrate data from multiple source systems, enabling a central view across the enterprise. This benefit is always valuable, but particularly so when the organization has grown by merger
• Improve data quality, by providing consistent codes and descriptions, flagging or even fixing bad data.
• Provide a single common data model for all data of interest regardless of the data's source
• Restructure the data so that it makes sense to the business users.
• Restructure the data so that it delivers excellent query performance, even for complex analytic queries, without impacting the operational systems
• Add value to operational business applications, notably customer relationship management (CRM) systems.