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twoski
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Homework Statement
Assume you are given the entity Person. This entity has 3 attributes: Name, Name of child, Name of parent.
Now, assume you want to modify your design of ”People” database above to include additional information about types of people such as sex, and people who are parents, etc. Use subclasses of people to represent these special types of people.
The Attempt at a Solution
There are 3 different entity sets we should start with: Person, Child and Parent. Person is the superclass which holds all generic information such as sex, name, age, etc.Parent and Child should both have the "Is-a" relationship to Person, but we need to also show that a child can be the child of a person, and a parent can be the parent of a person. Should this be introduced as an attribute of the "is-a" relationship? Does one of the relationships take precedent?
We also note that Parents have the "grandparent of" relationship to children.