Back to the Conceptual Data Model.
PURPOSE OF THESE FACTS :-
These FACTS define the functional requirements which the Database must meet.
They form the basis for agreement between the User and the Database Designer and are
written in a form of structured English which is clear and unambiguous.
The Draft FACTS have been defined and are detailed here ...
A. The Area being Modelled is :-
User Requirements :-
A Database to follow up Maintenance Contracts with Customers.
The main goal is to be able to get a list out of this DB each month that
shows them for which customers they will need to undertake some action
(e.g. to renew their software subscriptions, to renew licences, ...).
In the future, they would also like to publish this information towards
their customers on an Extranet, so that a customer can have a look
whenever he wants so that he immediately can see which products he has
bought from that Company and when he may expect some action and for what
B. The Things of Interest, ('THINGS'), include :-
B.2 Customer Actions
B.3 Maintenance Contracts
B.6 Suppliers Websites
C. These THINGS_OF_INTEREST are Related as follows :-
C.1 Each Customer buys one or many Products.
C.2 Each Customer can have none, zero or many Maintenance Contracts.
C.3 Each Customer takes zero, one or many Customer Actions at intervals.
C.4 Each Contract covers one and only one Product.
C.5 Each Product can be supplied by one or many Suppliers.
D. What else do we know about the THINGS_OF_INTEREST :-
D.1 Each Contract has a certain period for which it is valid.
E. Sample Data includes :-
E.1 To be determined
F. Typical Enquiries include :-
F.1 To be determined.
G.Miscellaneous Facts :-
G.1 Each Product can be found on a particular (Suppliers) website
G.2 Each Supplier has his products shown on a certain website
16th. December 2001