Characteristics of DWSubject-orient

Characteristics of DW
Subject-oriented. Data are organized by detailed subject, such as sales, products, or customers, containing only information relevant for decision support that allows decision makers to both know how their business performs and why.
A DW differs from typical DBs that they are more product-oriented and are tuned to handle transactions of DBs. Subject orientation allows a more comprehensive view of organization
Integrated. Data are from different sources and must be in a consistent form. DWs must deal with naming conflicts and discrepancies among units of measure.
Time variant (time series). A DW usually contains historical data (containing multiple time points, e.g. daily, weekly, monthly), except in real-time systems. They detect trends, deviations, long-term relationships for forecasting and comparisons, leading to decision making.
Nonvolatile. Users cannot change data in DWs. Obsolete data are discarded, and changes are recorded as new data.