Modern Database Management
13th Edition
ISBN: 9780134773650
Author: Hoffer
Publisher: PEARSON
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Chapter 8, Problem 8.49PAE
When a student has not chosen a major at a university, the university often enters a value of “Undecided” for the major field. Is “Undecided” a way to represent the null value? Should it be used as a default value? Justify your answer carefully.
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Chapter 8 Solutions
Modern Database Management
Ch. 8 - Prob. 8.1RQCh. 8 - Prob. 8.2RQCh. 8 - Prob. 8.3RQCh. 8 - Prob. 8.4RQCh. 8 - Prob. 8.5RQCh. 8 - Prob. 8.6RQCh. 8 - Prob. 8.7RQCh. 8 - Prob. 8.8RQCh. 8 - Explain why you sometimes have to reserve much...Ch. 8 - Why are field values sometimes coded?
Ch. 8 - Prob. 8.11RQCh. 8 - Prob. 8.12RQCh. 8 - Explain why normalized relations may not comprise...Ch. 8 - Prob. 8.14RQCh. 8 - List three common situations that suggest that...Ch. 8 - Explain the reasons why some experts are against...Ch. 8 - Prob. 8.17RQCh. 8 - Prob. 8.18RQCh. 8 - Prob. 8.19RQCh. 8 - Prob. 8.20RQCh. 8 - Prob. 8.21RQCh. 8 - Prob. 8.22RQCh. 8 - One of the strongest recommendations regarding...Ch. 8 - Explain why an index is useful only if there is...Ch. 8 - Indexing can clearly be very beneficial. Why...Ch. 8 - Prob. 8.26RQCh. 8 - Prob. 8.27RQCh. 8 - Describe the role of data dictionary in the...Ch. 8 - Prob. 8.29RQCh. 8 - Prob. 8.30RQCh. 8 - Explain how creating a view may increase data...Ch. 8 - Prob. 8.32RQCh. 8 - Prob. 8.33RQCh. 8 - Prob. 8.34RQCh. 8 - Prob. 8.35RQCh. 8 - Prob. 8.36RQCh. 8 - Prob. 8.37RQCh. 8 - Prob. 8.38RQCh. 8 - Prob. 8.39RQCh. 8 - How can views be used as part of data security?...Ch. 8 - Prob. 8.41RQCh. 8 - Prob. 8.42RQCh. 8 - Consider the following two relations for...Ch. 8 - Prob. 8.44PAECh. 8 - Prob. 8.45PAECh. 8 - Prob. 8.46PAECh. 8 - Prob. 8.47PAECh. 8 - Suppose you are designing a default value for the...Ch. 8 - When a student has not chosen a major at a...Ch. 8 - Prob. 8.50PAECh. 8 - Prob. 8.51PAECh. 8 - Consider the relations in Problem and Exercise...Ch. 8 - Prob. 8.53PAECh. 8 - Prob. 8.54PAECh. 8 - Prob. 8.55PAECh. 8 - Prob. 8.56PAECh. 8 - Prob. 8.57PAECh. 8 - Consider the relations specified in Problem and...Ch. 8 - Prob. 8.59PAECh. 8 - Prob. 8.60PAECh. 8 - Prob. 8.61PAECh. 8 - Prob. 8.62PAECh. 8 - Prob. 8.63PAECh. 8 - Prob. 8.64PAECh. 8 - Problems and Exercises 8-65 through 8-68 refer to...Ch. 8 - Prob. 8.66PAECh. 8 - Problems and Exercises 8-65i5 through 8-68 refer...Ch. 8 - Refer to Figure 4-5 0. For each of the following...Ch. 8 - Prob. 8.69PAECh. 8 - Prob. 8.70PAECh. 8 - Prob. 8.71PAECh. 8 - Prob. 8.72PAECh. 8 - Prob. 8.73PAECh. 8 - Prob. 8.74PAECh. 8 - Prob. 8.75PAECh. 8 - Prob. 8.76PAECh. 8 - Prob. 8.77PAE
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