In A Supertype/Subtype Hierarchy, Each Subtype Has:. We will consider only supertype and subtype hierarchies. Each subtype also inherits the primary key of the supertype.
PPT Chapter 4 The Enhanced ER Model PowerPoint Presentation, free from www.slideserve.com
An attribute of the supertype that determines the target subtype (s) is called the: An attribute of a supertype whose values determine the target subtype or subtypes. Each subtype also inherits the primary key of the supertype.
In A Supertype/Subtype Hierarchy, Each Subtype Has:
Hierarchies arise when an entity type appears as a subtype of only one supertype. We will consider only supertype and subtype hierarchies. Not exactly an answer to your question, but, what you are describing is not what most modelers would refer to as a supertype.
Define One Vehicle Entity Type To Hold All Entities.
1) each supertype has only one. Each subtype has only one attribute. Each subtype has only one.
A Supertype Is A Generic Entity Type That Has A Relationship With One Or More Subtypes.
B) each supertype has only one attribute. A supertype/subtype hierarchy has which of the following features? Supertype is an entity type that has got relationship (parent to child.
If A Supertype Participates In A Relationship Then All Of Its Subtypes Also Participate In That Relationship.
Each subtype also inherits the primary key of the supertype. Erd with peter chen notation. The third step in the data modeling process with a packaged data model is:
Important Points Here Are That.
Can a subtype have a subtype? Attributes that are common to a supertype and its subtypes are only shown at the supertype. Can a subtype have a subtype?
0 comments
Post a Comment