Modern Database Management (12th Edition)
12th Edition
ISBN: 9780133544619
Author: Jeffrey A. Hoffer, Ramesh Venkataraman, Heikki Topi
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Textbook Question
Chapter 5, Problem 5.33PAE
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.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
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.
Explain whether "undecidable" is a way to represent null value or default value if a student has not chosen a major at a university and the value of "undecided" is entered for the major field.
It is possible to have both a primary key and a candidate key for the same attribute.
Chapter 5 Solutions
Modern Database Management (12th Edition)
Ch. 5 - Prob. 5.1RQCh. 5 - Prob. 5.2RQCh. 5 - Prob. 5.3RQCh. 5 - Prob. 5.4RQCh. 5 - Prob. 5.5RQCh. 5 - Prob. 5.6RQCh. 5 - Prob. 5.7RQCh. 5 - Prob. 5.8RQCh. 5 - Explain why you sometimes have to reserve much...Ch. 5 - Why are field values sometimes coded?
Ch. 5 - Prob. 5.11RQCh. 5 - Prob. 5.12RQCh. 5 - Explain why normalized relations may not comprise...Ch. 5 - Prob. 5.14RQCh. 5 - List three common situations that suggest that...Ch. 5 - Explain the reasons why some experts are against...Ch. 5 - Prob. 5.17RQCh. 5 - Prob. 5.18RQCh. 5 - Prob. 5.19RQCh. 5 - Prob. 5.20RQCh. 5 - Prob. 5.21RQCh. 5 - State nine rules of thumb for choosing indexes.Ch. 5 - One of the strongest recommendations regarding...Ch. 5 - Explain why an index is useful only if there is...Ch. 5 - Indexing can clearly be very beneficial. Why...Ch. 5 - Consider the following two relations for...Ch. 5 - Prob. 5.28PAECh. 5 - Prob. 5.29PAECh. 5 - Prob. 5.30PAECh. 5 - Prob. 5.31PAECh. 5 - Suppose you are designing a default value for the...Ch. 5 - When a student has not chosen a major at a...Ch. 5 - Prob. 5.34PAECh. 5 - Prob. 5.35PAECh. 5 - Consider the relations in Problem and Exercise...Ch. 5 - Prob. 5.37PAECh. 5 - Prob. 5.38PAECh. 5 - Prob. 5.39PAECh. 5 - Prob. 5.40PAECh. 5 - Prob. 5.41PAECh. 5 - Consider the relations specified in Problem and...Ch. 5 - Prob. 5.43PAECh. 5 - Prob. 5.44PAECh. 5 - Prob. 5.45PAECh. 5 - Prob. 5.46PAECh. 5 - Prob. 5.47PAECh. 5 - Problems and Exercises 8-65 through 8-68 refer to...Ch. 5 - Refer to the large Pine Valley Furniture Company...Ch. 5 - Problems and Exercises 8-65i5 through 8-68 refer...Ch. 5 - Refer to Figure 4-5 0. For each of the following...
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.Similar questions
- Given the following ERD. ID name salary Instructor Grades teaches ID name salary Student 1) What is the descriptive attribute of the relationship between instructor and student? 2) Is this relationship a one-to-one, a one-to-many, or a many-to-many relationship?arrow_forwardA variable cannot be sufficiently described by the word "type." Or to put it another way, every variable has some kind of attributes and data types. What is the best approach to describe any variable's characteristics using the notion that makes this possible?arrow_forwardWhen defining a variable, just using the word "Type" is not sufficient. To put it another way, every variable has a number of data types in addition to a plethora of other attributes. How can the features of any variable be communicated using the concept that enables us to do so in the most effective manner possible?arrow_forward
- What exactly is meant by the term "partial dependence," and how does it function? What is the typical shape that it takes, and how is it related with it?arrow_forwardA derived attribute can be stored in a table or calculated on each occasion that it is required. An example of a derived attribute is your Grade Point Average which is calculated by adding together a score for each unit (e.g., HD=4, D=3, C=2, P=1, N=0) and dividing that by the number of units you have completed. Explain how the decision as to whether the Grade Point Average would be stored in a table or calculated would be made. You are administering a database in a large retail company that records sales at each of the company’s stores. Tuning the database to improve performance by adding indexes and optimising query execution is an important ongoing aspect of the physical database design. Which attributes in a database such as this (apart from the primary key) are likely to BENEFIT from being indexed? Which attributes would you generally avoid indexing, and why?arrow_forwardWhen a student has not selected a major at a university, the university typically puts a value of "Undecided" for the major field. Is "Undecided" a method to express the null value? Should it be used as a default value? Justify your answer carefully.arrow_forward
- The definition of a variable is required to contain, in addition to the variable's name, the variable's "type" as well as the variable's "additional attributes." Every variable may be assigned to more than one data type. If you could describe the concept, would it be possible for us to more accurately define any variables in the future?arrow_forwardA college course may have one or more scheduled sections or may not have a scheduled section. Attributes of COURSE include Course ID, Course Name, and Units. Attributes of SECTION include Section Number and Semester ID. Semester ID is composed of two parts: Semester and Year. Section Number is an integer (such as 1 or 2) that distinguishes one section from another for the same course but does not uniquely identify a section. How did you model SECTION? Why did you choose this way versus alternative ways to model SECTION?arrow_forwarda. What is Attribute Driven Design? Describe the process. b. What resources are needed before Attribute Driven Design process can start? c. What is the output of the Attribute Driven Design process?arrow_forward
- It's possible to have a main key and a candidate key for the same characteristic.arrow_forwardA parameter comes from where while a statistic comes from where?arrow_forwardTo completely define a variable, not just its 'type' but also its other characteristics' must be mentioned. To put it another way, all variables have a data type as well as other attributes. Explain the concept that will allow us to describe any variable's attributes.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Np Ms Office 365/Excel 2016 I NtermedComputer ScienceISBN:9781337508841Author:CareyPublisher:Cengage
Np Ms Office 365/Excel 2016 I Ntermed
Computer Science
ISBN:9781337508841
Author:Carey
Publisher:Cengage
dml in sql with examples; Author: Education 4u;https://www.youtube.com/watch?v=WvOseanUdk4;License: Standard YouTube License, CC-BY