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

Silverston c09.tex V2 - 11/21/2008 3:16am Page 483

Application Data Models 483

Synopsis

This section dealt with the beginning of the development of a customer

information system for Sands Distribution. The data team created a simple,

specific data model as part of a scope statement to start the discussions and the

data modeling around customer data. The data model captured the common

terminology and the attributes that were important to Sands Distribution.

After the data modelers used the first data model to get feedback from

subject matter experts, additional requirements emerged. The data modelers

then expanded the model in Figure 9-1 and created the data model that would

be used for the initial prototype (Figure 9-2). This was a little more flexible

model than the model shown in Figure 9-1.

The enhanced data model was quickly created by replacing a couple

of the level 1 patterns with level 2 patterns. For example, in Figure 9-

2, the classification attributes of Figure 9-1 became entities in their own

right, a many-to-many relationship was created to allow multiple indus-

try classifications for a customer, an additional contextual role entity was

added to allow the parent company to be the bill-to customer, and sta-

tuses were maintained in their own STATUS TYPE entity. This created a

good baseline for communication with the business and IT, and a more

flexible initial data model, which could be used ...