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

Silverston c07.tex V2 - 11/20/2008 5:44pm Page 324

324 Chapter 7 ■ Contact Mechanisms: How to Get in Touch

The Level 1 Contact Mechanism Pattern may be used to better understand

and validate the specific data requirements. It is very useful at explicitly

showing all of the different types (purpose and usage) of contact mechanisms

for an area of interest. It provides two useful aids for describing a subject area.

First, it provides a clear and unambiguous view of the contact mechanism types

for a subject area. Second, it highlights the different ways that the same concept

may be viewed by different areas of the business. For example, Figure 7-2

accommodates the PARTY contact mechanism attributes of the secretarial

staff, which were very different from the ORDER contact mechanism attributes

described by accounting and operations staff. This can be a strong indicator

of problems of understanding and consistency in an enterprise. The pattern

also helps provide a very e asy way to start the modeling process and begins

to uncover the needs and terminology that different parts of the enterprise use

when talking about contact mechanisms.

The Level 1 Contact Mechanism Pattern can be implemented, and has been,

but beware! Usage of this pattern for implementations has several drawbacks:

It does not accommodate changes to information requirements very easily,

attributes may get repeated redundantly, and there ...