is prohibited.
fact is graphically represented by a box with two sections, one for the
fact name and one for the measures.
Examples of facts in the trade domain are sales, shipments, purchases, claims; in
the financial domain: stock exchange transactions, contracts for insurance policies,
granting of loans, bank statements, credit cards purchases. It is essential for a fact
to have some dynamic aspects, that is, to evolve somehow across time.
Guideline.1: The concepts represented in the data source by frequentlyupdated
archives are good candidates for facts; those represented by
almost-static archives are not.
As a matter of fact, very few things are completely static; even the relationship
between cities and regions might change, if some border were revised. Thus, the
choice of facts should be based either on the average periodicity of changes, or on
the specific interests of analysis. For instance, assigning a new sales manager to a
sales department occurs less frequently than coupling a promotion to a product; thus,
while the relationship between promotions and products is a good candidate to be
modeled as a fact, that between sales managers and departments is not??”except for
the personnel manager, who is interested in analyzing the turnover!
Definition 2: A measure is a numerical property of a fact, and describes
one of its quantitative aspects of interests for analysis.
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