9+ the following diagram is an example of a supertype/subtype hierarchy.

Use of a supertypesubtype relationship is necessary when which of the following exists. Creating a Generalization Hierarchy The supertype is also assigned an attribute called a discriminator whose values.

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B hierarchical data model.

. 67 In a supertypesubtype hierarchy attributes are assigned at the highest logical level that is. Works_in EMPLOYEE DEPARTMENT True O False Question 16 2. A simple practical example of subtypes is shown in the diagram right.

The type bird has three subtypes duck cuckoo and ostrich. Conceptually each of these is a variety of the. For the relationship represented in the figure below a department can have more than one employee.

Discuss how attributes are assigned in a supertypesubtype hierarchy. Specifically if T2 is a subtype of T1 program elements designed to operate on. When a subtype entity inherits values of the supertype attribute.

What are reasons for creating OSPF in a hierarchical design. An instance of a subtype participates in a relationship that is unique to that. 35 The figure below is an example of an.

Attributes are assigned at the highest logical level that is possible in the hierarchy. 1To decrease routing overhead 2To speed up convergence 3To confine network instability to. Neither IE nor IDEF1X directly allow specifying abstract vs.

When a supertype entity inherits values of another. 36 An entity cluster can be formed by. There are different ways that supertypes and subtypes can be shown on an Entity Relationship diagram ERD or.

Study with Quizlet and memorize flashcards containing terms like supertypesubtype hierarchy A ________ addresses whether an instance of a supertype may simultaneously be a member of. Which of the following is correct. 66 The following diagram is an example of a supertypesubtype hierarchy.

The following diagram from the ERwin Methods Guide Chapter 5 Subtype Relationships illustrates the difference. B1 Drawing Supertypes and Subtypes on the Entity Relationship Diagram. When a supertype entity inherits values of the subtype attribute.

The relationship between a supertype and any of its subtypes involves the notion of substitutability. How attributes are assigned in a supertype subtype hierarchy.

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