 Show Chapter 5, Problem 1RQ Want to see more full solutions like this?Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts! Knowledge Booster Learn more about Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, computer-science and related others by exploring similar questions and additional content below. Recommended textbooks for you Database Systems: Design, Implementation, & Manag... ISBN:9781285196145 Author:Steven, Steven Morris, Carlos Coronel, Carlos, Coronel, Carlos; Morris, Carlos Coronel and Steven Morris, Carlos Coronel; Steven Morris, Steven Morris; Carlos Coronel Publisher:Cengage Learning Database Systems: Design, Implementation, & Manag... ISBN:9781305627482 Author:Carlos Coronel, Steven Morris Publisher:Cengage Learning Principles of Information Systems (MindTap Course... ISBN:9781285867168 Author:Ralph Stair, George Reynolds Publisher:Cengage Learning Fundamentals of Information Systems ISBN:9781337097536 Author:Ralph Stair, George Reynolds Publisher:Cengage Learning Principles of Information Systems (MindTap Course... ISBN:9781305971776 Author:Ralph Stair, George Reynolds Publisher:Cengage Learning Oracle 12c: SQL ISBN:9781305251038 Author:Joan Casteel Publisher:Cengage Learning Database Systems: Design, Implementation, & Manag... ISBN:9781285196145 Author:Steven, Steven Morris, Carlos Coronel, Carlos, Coronel, Carlos; Morris, Carlos Coronel and Steven Morris, Carlos Coronel; Steven Morris, Steven Morris; Carlos Coronel Publisher:Cengage Learning Database Systems: Design, Implementation, & Manag... ISBN:9781305627482 Author:Carlos Coronel, Steven Morris Publisher:Cengage Learning Principles of Information Systems (MindTap Course... ISBN:9781285867168 Author:Ralph Stair, George Reynolds Publisher:Cengage Learning Fundamentals of Information Systems ISBN:9781337097536 Author:Ralph Stair, George Reynolds Publisher:Cengage Learning Principles of Information Systems (MindTap Course... ISBN:9781305971776 Author:Ralph Stair, George Reynolds Publisher:Cengage Learning Oracle 12c: SQL ISBN:9781305251038 Author:Joan Casteel Publisher:Cengage Learning What defines the relationship between a supertype entity and the subtype entities?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.
What can be said about supertype and subtype?Supertype is an entity type that has got relationship (parent to child relationship) with one or more subtypes and it contains attributes that are common to its subtypes. Subtypes are subgroups of the supertype entity and have unique attributes, but they will be different from each subtype.
What are the two conditions for using Supertype subtype relationships?Use supertype/subtype relationships if have one or both of the following: 1) There are attributes that apply to some (but not all) instances of an entity type. 2) The instances of a subtype participate in a relationship unique to that subtype.
What is a subtype relationship?A subtype relationship connects an entity that defines the category and two or more additional entities that define each of the elements of the category. The parent entity of the category is considered the supertype and each child entity is considered a subtype.
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What kind of relationship is shared between an entity supertype and its subtypes?
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