Database Concepts (8th Edition)
8th Edition
ISBN: 9780134601533
Author: David M. Kroenke, David J. Auer, Scott L. Vandenberg, Robert C. Yoder
Publisher: PEARSON
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Textbook Question
Chapter 4, Problem 4.10RQ
Define the term identifier, and indicate which attribute(s) defined in your answer to question 4.9 identifies the entity.
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Explain entity sets.
The entity type STUDENT has the following attributes: Student Name, Address, Phone, Age, Activity, and No of Years. Activity represents some campus-based student activity, and No of Years represents the number of years the student has engaged in this activity. A given student may engage in more than one activity. Draw an ERD for this situation. What attribute or attributes did you designate as the identifier for the STUDENT entity? Why?
Explain the usage of attributes and the generic name for attribute in the relationship model.
Chapter 4 Solutions
Database Concepts (8th Edition)
Ch. 4 - Prob. 4.1RQCh. 4 - Prob. 4.2RQCh. 4 - Prob. 4.3RQCh. 4 - What is a use case, and what is its purpose?Ch. 4 - Give an example of a data constraint.Ch. 4 - Prob. 4.6RQCh. 4 - Define the term entity, and give an example other...Ch. 4 - Explain the difference between an entity class and...Ch. 4 - Define the term attribute, and give examples for...Ch. 4 - Define the term identifier, and indicate which...
Ch. 4 - Prob. 4.11RQCh. 4 - Prob. 4.12RQCh. 4 - Prob. 4.13RQCh. 4 - Prob. 4.14RQCh. 4 - List and give an example of the three types of...Ch. 4 - Prob. 4.16RQCh. 4 - Prob. 4.17RQCh. 4 - Prob. 4.18RQCh. 4 - Define the term weak entity, and give an example...Ch. 4 - Explain the ambiguity in the definition of the...Ch. 4 - Define the term associative entity, and give an...Ch. 4 - Define the terms supertype, subtype, and...Ch. 4 - What is an exclusive subtype relationship? Give an...Ch. 4 - What is an inclusive subtype relationship? Give an...Ch. 4 - Prob. 4.25RQCh. 4 - Prob. 4.26RQCh. 4 - Prob. 4.27RQCh. 4 - Prob. 4.28RQ
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