When to Design a Data Model

Ideally, you would want to have a well designed data model at the beginning of your project. In practice though, that may not be the case. Here are some points that we may need to plan for:

• We cannot guarantee the model won't need to be changed over time
• We may not know which table becomes large over time and may need tuning
• We may not know the usage of the models by the application(s) over time

The answer to the question of when to design a data model is to try to design it well at the beginning and then re-evaluate when:

You Notice That

• The data model is hard to develop against
• New requirements require changes to the model

You Monitor For

• Long running queries that include that table
• Locking queries that run against the that table

You Track When

• The table becomes too big
• The table becomes more difficult to maintain