Binary vs. Ternary Relationships

• If each policy is owned by just 1 employee:

  • Key constraint on Policies would mean policy can only cover 1 dependent!

• What are the additional constraints in the 2nd diagram?

age

pname

Dependents

Covers

age

pname

Dependents

Purchaser

Bad design

Better design

Previous slide

Next slide

Back to first slide

View graphic version