A Data Dimension is a set of data attributes pertaining to something of interest to a
business. Dimensions are things like "customers", "products", "stores"
and "time". For users of Data Warehouses, data dimensions are entry
points to numeric facts (e.g. sale, profit, revenue) that a business wishes
to
monitor.
For example, a business might want to know how may blue widgets were sold at a specific store in Los Angeles last month.
A data dimension can be hierarchical. For example, "days" can be
grouped into "months", "months" into "quarters" and quarters into "fiscal
years" or "calendar years". This allows fact data to be easily aggregated,
summarized and presented.
