7.3 A Logical Data-Modeling Methodology

We now have a completed logical data model. Let's review the process we went through to get here.

1. Identify and model the entities.

2. Identify and model the relationships between the entities.

3. Identify and model the attributes.

4. Identify unique identifiers for each entity.

5. Normalize.

In practice, the process is rarely so linear. As shown in the example, it is often tempting and appropriate to jump around between entities, relationships, attributes, and unique identifiers. It is not as important that you follow a strict process as it is that you discover and capture all the information necessary to correctly model the system.

The data model we created in this chapter is quite simple. We created a model representative of the type and complexity of databases you are likely to encounter in developing MySQL databases. We did not cover a whole host of design techniques and concepts that are less important to small-scale database design, but these can be found in any text dedicated to database design.