Graded Quiz 3 - Unit 3 PDF

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Unit 3...

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Which of the following is not a goal of normalization? Select one: a. Simplifying the enforcement of referential integrity b. Maintaining data effectively c. Maximizing data storage space d. Minimizing data redundancy Feedback

Your answer is correct. The correct answer is: Maximizing data storage space Question 2 Correct Mark 1.00 out of 1.00

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Which of the following is wrong about the functional dependency A → (B, C, D)? Select one: a. B, C, and D together determine A b. C is functionally dependent on A.

c. A determines D. d. B, C, and D are functionally dependent on A Feedback

Your answer is correct. The correct answer is: B, C, and D together determine A Question 3 Correct Mark 1.00 out of 1.00

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For the relationship represented in the figure below, which of the following is wrong?

Select one: a. An instructor does not have to teach any course. b. A course can be taught by more than one instructor. c. An instructor can teach more than one course. d. A course has to be taught by one instructor Feedback

Your answer is correct.

The correct answer is: A course can be taught by more than one instructor. Question 4 Correct Mark 1.00 out of 1.00

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In an Entity-Relationship model, which concept is generally used to represent an instructor? Select one: a. Attribute b. Entity c. Relationship set d. Constraint Feedback

Your answer is correct. The correct answer is: Entity Question 5 Correct Mark 1.00 out of 1.00

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Which of the following is wrong about domains of a relation? Select one: a. Two or more attributes can be defined on the same domain b. A tuple can draw values from different domains c. Two attributes that include values from different domains can easily be compared d. A pool of atomic values constitutes a domain Feedback

Your answer is correct. The correct answer is: Two attributes that include values from different domains can easily be compared Question 6 Correct Mark 1.00 out of 1.00

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Which of the following statements is wrong? Select one: a. A relational database can be defined as a selfdescribing collection of non-integrated relations. b.

Both the primary key and a candidate key can uniquely identify the tuples in a relation. c. Physical model includes the lowest level of abstractions d. A relational database stores data in the form of relations. Feedback

Your answer is correct. The correct answer is: A relational database can be defined as a self-describing collection of nonintegrated relations. Question 7 Correct Mark 1.00 out of 1.00

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Two attributes that include values from different domains can easily be compared. Select one: True False Feedback

The correct answer is 'False'. Question 8 Incorrect Mark 0.00 out of 1.00

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“A student can attend six courses, each with a different instructor. Each instructor teaches at least 3 courses.” What is the type of relationship between students and instructors? Select one: a. one-to-one b. one-to-many c. many-to-many d. None of the above Feedback

Your answer is incorrect. The correct answer is: many-to-many Question 9 Correct Mark 1.00 out of 1.00

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Which of the following is true about a relation? Select one: a. A relation is a one-dimensional table b. There is a single attribute in each relation

c. All the values in any column must be of the same type. d. The order of the tuples of a relation is determined by the primary key Feedback

Your answer is correct. The correct answer is: All the values in any column must be of the same type. Question 10 Correct Mark 1.00 out of 1.00

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Considering the below E-R diagram. Which of the following statements is wrong?

Select one:

a. A customer has to give his/her phone number. b. For each sale, tax has to be calculated. c. Each item has to have a description. d. The store has to provide its phone number. Feedback

Your answer is correct. The correct answer is: A customer has to give his/her phone number. Question 11 Correct Mark 1.00 out of 1.00

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Which of the following statements is correct? Select one: a. Two or more attributes can be defined on the same domain. b. A relation is in the first normal form if it has no more than one multivalued attribute. c. There is a single attribute in each relation

d. A surrogate key is an attribute or set of attributes that uniquely identifies a record in a relation Feedback

Your answer is correct. The correct answer is: Two or more attributes can be defined on the same domain. Question 12 Incorrect Mark 0.00 out of 1.00

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A primary key of a relation should be part of every other relation to provide referential integrity. Select one: True False Feedback

The correct answer is 'False'. Question 13 Correct Mark 1.00 out of 1.00

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A Database Administrator is responsible for developing logical data model. Select one: True False Feedback

The correct answer is 'False'. Question 14 Correct Mark 1.00 out of 1.00

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For the relationship represented in the figure below, which of the following is wrong?

Select one: a. An instructor does not have to teach any course. b. A course can be taught by more than one instructor. c. A course has to be taught by more than one instructor d. An instructor can teach more than one course. Feedback

Your answer is correct. The correct answer is: A course has to be taught by more than one instructor Question 15 Correct Mark 1.00 out of 1.00

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Which of the following is always correct? Select one: a. If A → B and C is another attribute, then AB → C b. If A → BC, then A → B and B → C c. If A → B and A → C, then A → BC d. If A → B and A → C, then B → C Feedback

Your answer is correct. The correct answer is: If A → B and A → C, then A → BC...