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I am drawing the conceptual data model between vehicle, car and motorbike. As far as I know.

Hierarchy. The simple "is a" feature.

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Disjunction means that each ocurrence of superentity should only one subentity. Its notation is a "d" inside the triangle

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Total restriction means that each ocurrence of superentity (vehicle) should be a subentity (car or motorbike). Its notation is double line. In this case Im not sure what to put inside the triangle.

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Are all of them valid? Which of these notations are incorrect?

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  • The relevant standard methods with proper notation are Subtypes. You can find some info here and more detailed here. Commented Mar 13 at 7:30

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