Database Reference
In-Depth Information
Once we've identified the fact that two entities have a relationship, we need to articulate
what that relationship looks like and make it precise. To make it precise, we find ourselves
asking up to eight questions: two on participation, two on optionality, and up to four ques-
tions on subtyping. So after creating a template for our Survey example, I asked a business
expert each question and checked off the appropriate answer:
Question
Yes? No?
Can an Industry contain more than one Organization?
✓
Can an Organization operate in more than one Industry?
✓
Can an Industry exist without an Organization?
✓
Can an Organization exist without an Industry?
✓
Are there examples of Industry that would be valuable to show?
✓
Are there examples of Organization that would be valuable to show?
✓
Does an Industry go through a lifecycle?
✓
Does a Customer go through a lifecycle?
✓
Can an Organization create more than one Survey?
✓
Can a Survey be created by more than one Organization?
✓
Can an Organization exist without a Survey?
✓
Can a Survey exist without an Organization?
✓
