Modern Database Management
13th Edition
ISBN: 9780134773650
Author: Hoffer
Publisher: PEARSON
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Chapter 4, Problem 4.23RQ
Program Plan Intro
The conditions where a foreign key must not be null.
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A foreign key must not be null under what circumstances?]
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Chapter 4 Solutions
Modern Database Management
Ch. 4 - Define each of the following terms: determinant...Ch. 4 - Prob. 4.2RQCh. 4 - Prob. 4.3RQCh. 4 - Describe the primary differences between the...Ch. 4 - Summarize six important properties of relations.Ch. 4 - Describe two properties that each candidate key...Ch. 4 - Describe the three types of anomalies that can...Ch. 4 - Demonstrate each of the anomaly types with an...Ch. 4 - Fill in the blanks in each of the following...Ch. 4 - What is a well-structured relation? Why are...
Ch. 4 - Prob. 4.11RQCh. 4 - Describe how the following components of an E-R...Ch. 4 - Prob. 4.13RQCh. 4 - Prob. 4.14RQCh. 4 - Briefly describe four typical problems that often...Ch. 4 - Prob. 4.16RQCh. 4 - Explain how each of the following types of...Ch. 4 - Prob. 4.18RQCh. 4 - Prob. 4.19RQCh. 4 - Prob. 4.20RQCh. 4 - Prob. 4.21RQCh. 4 - What is the relationship between the primary key...Ch. 4 - Prob. 4.23RQCh. 4 - Explain what can be done with primary keys to...Ch. 4 - Prob. 4.25RQCh. 4 - Explain three conditions that suggest a surrogate...Ch. 4 - Prob. 4.27RQCh. 4 - For each of the following E-R diagrams from...Ch. 4 - Prob. 4.29PAECh. 4 - Prob. 4.30PAECh. 4 - For your answers to the following Problems and...Ch. 4 - Figure 4-3212 shows a class list for Millennium...Ch. 4 - Prob. 4.33PAECh. 4 - Prob. 4.34PAECh. 4 - Prob. 4.35PAECh. 4 - Prob. 4.36PAECh. 4 - Prob. 4.37PAECh. 4 - Prob. 4.38PAECh. 4 - Prob. 4.39PAECh. 4 - Transform Figure 2-15a, attribute version, to 3NF...Ch. 4 - The Public Safety office at Millennium College...Ch. 4 - Prob. 4.42PAECh. 4 - Prob. 4.43PAECh. 4 - Prob. 4.44PAECh. 4 - For your answers to Problem and Exercise 3-33 from...Ch. 4 - Prob. 4.46PAECh. 4 - Prob. 4.47PAECh. 4 - Figure 4-38 includes an EER diagram for a...Ch. 4 - Prob. 4.49PAECh. 4 - Prob. 4.50PAECh. 4 - Prob. 4.51PAECh. 4 - Prob. 4.52PAECh. 4 - Figure 4-40 shows an EER diagram for a university...Ch. 4 - Explore the data included in Table 4-9. Assume...Ch. 4 - Prob. 4.55PAECh. 4 - Prob. 4.56PAECh. 4 - Prob. 4.57PAECh. 4 - Prob. 4.58PAE
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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.Similar questions
- What is a foreign key constraint? Why are such constraints important? What is referential integrity?arrow_forwardWhat exactly is a foreign key in terms of database integrity? What can you say to support this stipulation?arrow_forwardHow exactly do foreign keys ensure that a database's integrity is preserved? What kind of proof do you have to back your claim?arrow_forward
- How does the foreign key contribute to the security of a database? Do you want to do this for a certain reason?arrow_forwardHow does the foreign key contribute to the security of a database? Do you want to do this for a particular reason?arrow_forwardWhy is a foreign key required to preserve the integrity of the database? Is there a justification for this's significance?arrow_forward
- In terms of database integrity, what does a foreign key mean? Is there anything you can say to explain why this is required?arrow_forwardWhy is a foreign key required to maintain the database's integrity? Is there a justification for its importance?arrow_forwardWhy is the foreign key important for the integrity of a database? Can you come up with a scenario to show why it is necessary?arrow_forward
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