Database Concepts (7th Edition)
7th Edition
ISBN: 9780133544626
Author: David M. Kroenke, David J. Auer
Publisher: PEARSON
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Chapter 4, Problem 4.25RQ
Explanation of Solution
Recursive relationship:
An entity which calls by itself more than once in different roles with a relationship are termed as a recursive relationship.
Example:
Consider the “Employee” can be in post of “Manager” and a “Manager” can manage an employee. So, “Manages” is relationship with “Employee” entity in recursive manner.
E-R diagram for the above example:
The following “E-R diagram” demonstrates an employee has a manager and the manager manages many employees.
Explanation:
Employee entity “1:M” relationship with “Manages” relationship which means an employee can be in the post of manager and a manager can manage many employees...
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Students have asked these similar questions
Write a program that simulates a Magic 8 Ball, which is a fortune-telling toy that displays a random response to a yes or no question. In the student sample programs for this book, you will find a text file named 8_ball_responses.txt. The file contains 12 responses, such as “I don’t think so”, “Yes, of course!”, “I’m not sure”, and so forth. The program should read the responses from the file into a list. It should prompt the user to ask a question, then display one of the responses, randomly selected from the list. The program should repeat until the user is ready to quit.
Contents of 8_ball_responses.txt:
Yes, of course! Without a doubt, yes. You can count on it. For sure! Ask me later. I'm not sure. I can't tell you right now. I'll tell you after my nap. No way! I don't think so. Without a doubt, no. The answer is clearly NO.
(You can access the Computer Science Portal at www.pearsonhighered.com/gaddis.)
Start with the initial angles within the integration and just integrate them without mapping them to specific quadrants. Use python and radians
How does encryption prevent a hacker from getting your data
Chapter 4 Solutions
Database Concepts (7th 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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