Which of the following is a generic entity type that has a relationship with one or more subtypes? Show
Given the following entities, which of the choices below would be the most complicated? Automobile: VIN, EngineSize, NumberOfDoors,
NumberOfPassengers, FuelType, Transmission Define one vehicle entity type to hold all entities. The property by which subtype entities possess the values of all attributes of a supertype is called: Subtypes should be used when: there are attributes that apply to some but not all instances of an entity type. The process of defining one or more subtypes of a supertype and forming relationships is called: The process of defining a more general entity type from a set of more specialized entity types is called: Which of the following is a completeness constraint? The ________ rule specifies that an entity instance of a supertype is allowed not to belong to any subtype. The ________ rule specifies that each entity instance of the supertype must be a member of some subtype in the relationship. A ________ constraint is a type of constraint that addresses whether an instance of a supertype must also be an instance of at least one subtype. The ________ rule specifies that an entity can be a member of only one subtype at a time. A ________ addresses whether an instance of a supertype may simultaneously be a member of two or more subtypes. disjointedness constraint What rule specifies that an entity instance of a supertype is not required to belong to a subtype?56) The total specialization rule states that an entity instance of a supertype is allowed not to belong to any subtype.
What type of constraints in Supertype that an instance of a supertype may simultaneously be a member of two or more subtypes *?Disjoint rule; overlap rule. With the disjoint rule an instance of a supertype may be a member of only one subtype at a given time. With the overlap rule an instance of a supertype may simultaneously be a member of two or more subtypes. Structural constraint; operational constraint.
What type of constraints in Supertype that an instance of a supertype must also be a member of at least one subtype?Completeness Constraints: Whether an instance of a supertype must also be a p yp member of at least one subtype. b) Partial Specialization rule Figure 3-6 Examples of completeness constraints (cont.)
Which of the following is a generic entity type that has a relationship with one or more subtypes?A supertype is a generic entity type that has a relationship with one or more subtypes. A subtype is a sub-grouping of the entities in an entity type that is meaningful to the organization and that shares common attributes or relationships distinct from other subgroups.
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Which of the following rules specifies that each entity instance of the supertype must be a member of some subtype in the relationship?
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