Discuss the reasoning behind using supertype/subtype relationships
What will be an ideal response?
It is best to use a supertype/subtype hierarchy when there are attributes that apply to some but not all instances of an entity type. For example, if we have an employee entity type and there is an hourly wage attribute that only applies to hourly employees, it may be best to use a supertype/subtype relationship. Another reason for using supertype/subtype relationships is when you have instances of a subtype that participate in a relationship unique to that subtype. For example, if we have a contractor subtype of employee that has a relationship with staffing agency, then it would be best to use supertype/subtype relationship.
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Indicate whether the statement is true or false