The glut of information was dulling awareness, not aiding it
--Jerry Mander
The aggregate tables enhance reporting performance1 by reducing
the amount of data that needs to be queried for widely used
reports. Aggregate awareness at the database or the query tool
makes the use of aggregate tables transparent to the user of the
data warehouse.
Consider the example star schema for a financial services company as a
simple case for aggregations:
|
Account (customer) 30 million records |
|
|
|
Product |
|
|
\ |
|
/ … |