The Data Model Resource Book, Volume 3: Universal Patterns for Data Modeling

Silverston c07.tex V2 - 11/20/2008 5:44pm Page 379

Level 4 Contact Mechanism Pattern 379

does not have an email address would have the capability to store email

addresses. An entity would also have available every purpose type and

usage type. For example, a SHIPMENT entity would be able to associate

a ‘‘Technical support’’ purpose or a ‘‘Personal’’ usage type when these

classifications may not make sense for a SHIPMENT. To accommodate

this, you could enhance this pattern with one of the rules patterns in

this book and there could be a business rules layer to enforce rules, such

as what purposes and usages are allowed for specific types of contact

mechanisms.

6

Because it is a generalized approach, it is easier for data modelers to

become ‘lazy.’ Becauseoftheflexiblenatureofthispatternitiseasyfor

data modelers to forego the analysis of new contact mechanisms and

contact mechanism classifications and just ‘attach’ any new entity that

needs contact mechanisms to this data model structure.

This pattern is generalized and abstract and thus more difficult to

understand. This pattern may be difficult for many to understand

because it is abstract, and in our opinion, it would not be a very effective

model for gathering and validating data requirements or to help define

scope.

Synopsis

The Level 4 Contact Mechanism Pattern is the most flexible ‘plug-and-play

pattern’ that can be used by an enterprise to automatically ...