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CS403: Certiﬁcate Final Exam: Attempt review | Saylor Academy

https://learn.saylor.org/mod/quiz/review.php?attempt=1556761&cmid=23178&showall=1

Back to 'Certificate Final Exam\'

Started on	Saturday, March 26, 2022, 10:19 PM

State	Finished

Completed on	Saturday, March 26, 2022, 10:21 PM

Time taken	2 mins 26 secs

Points	12.00/50.00

Grade	2.40 out of 10.00 (24%)

Question 1

Incorrect

0.00 points out of 1.00

Which of the following is information?

Select one: a. 32

b. It is 32.

c. It is 32 degrees.

d. It is 32 degrees Fahrenheit.

Question 2	What is one of the disadvantages of file processing systems?

Incorrect
0.00 points out	Select one:
of 1.00		a.	Low data quality
		a.	Low data quality
		b.	Limited data sharing
		b.	Limited data sharing
		c.	Short development time
		d.	Program-data independence


Question 3	Which of the following selections best describes information?

Incorrect
0.00 points out	Select one:
of 1.00		a.	Letters
		a.	Letters
		b.	Data plus semantics
		b.	Data plus semantics
		c.	Letters that spell a word
		c.	Letters that spell a word
		d.	A number and its data type


Question 4	What are databases generally used for today?
	What are databases generally used for today?
Incorrect
0.00 points out	Select one:
of 1.00		a.	Backing up hard drives or other storage disks
		a.	Backing up hard drives or other storage disks
		b.	Recording the behavior of real time embedded systems
		c.	Storing and retrieving enterprise data for business systems
		c.	Storing and retrieving enterprise data for business systems
		d.	Performing computations for scientific and engineering application systems

1 of 15

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Question 5	Which of the following best describes a database?
	Which of the following best describes a database?
Incorrect
0.00 points out	Select one:
of 1.00		a.	A system for managing data
		a.	A system for managing data
		b.	A set of data for a particular application
		c.	A major subsystem of an operating system
		d.	A reusable, organized collection of related data
		d.	A reusable, organized collection of related data


Question 6	One function of a DBMS is provision of which of the following?

Correct
1.00 points out	Select one:
of 1.00		a.	Data security
		a.	Data security
		b.	Data accuracy
		c.	Data redundancy
		d.	Data dependence


Question 7	To support concurrent transactions, a DBMS should have which of the following properties?

Correct
1.00 points out	Select one:
of 1.00		a.	atomicity, durability, and isolation
		a.	atomicity, durability, and isolation
		b.	atomicity, irreducibility, and isolation
		c.	durability, irreducibility, and isolation
		c.	durability, irreducibility, and isolation
		d.	atomicity, durability, and irreducibility


Question 8	Which of the following are generic database architectures?
	Which of the following are generic database architectures?
Incorrect
0.00 points out	Select one:
of 1.00		a.	Distributed and leased
		a.	Distributed and leased
		b.	Centralized and leased
		b.	Centralized and leased
		c.	Centralized and distributed
		d.	Centralized and networked


Question 9	What kind of database corresponds to 'table'?
	What kind of database corresponds to 'table'?
Incorrect
0.00 points out	Select one:
of 1.00		a.	Network
		a.	Network
		b.	Relational
		c.	Hierarchical
		c.	Hierarchical
		d.	Object-oriented

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Question 10	Which of the following describes the capability to change the physical schema of a database without having to rewrite application programs?

Incorrect
0.00 points out	Select one:
of 1.00		a.	Logical data independence
		a.	Logical data independence
		b.	Physical data dependence
		c.	Physical data independence
		d.	Physical schema refinement
		d.	Physical schema refinement


Question 11	Logical data independence allows modifications of what without rewriting application programs?

Incorrect
0.00 points out	Select one:
of 1.00		a.	User view
		a.	User view
		b.	Table contents
		c.	Logical schema
		d.	Physical schema


Question 12	What are rules that are valid for information in a database called?

Incorrect
0.00 points out	Select one:
of 1.00		a.	constructs
		a.	constructs
		b.	constraints
		c.	foreign keys
		c.	foreign keys
		d.	primary keys


Question 13	Indices are useful for searching a database because they decrease which of the following?

Incorrect
0.00 points out	Select one:
of 1.00		a.	query complexity
		a.	query complexity
		b.	search time for certain types of queries
		b.	search time for certain types of queries
		c.	the amount of storage used in searching a database
		d.	the design effort needed for developing the database search algorithms


Question 14	What is a value that a DBMS maps to a single element of a relation?

Correct
1.00 points out	Select one:
of 1.00		a.	a key
		a.	a key
		b.	a field value
		c.	a field name
		c.	a field name
		d.	a query value

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Question 15	IMS is an example of a database system that implemented which of the following models?

Correct
1.00 points out	Select one:
of 1.00		a.	Hierarchical
		a.	Hierarchical
		b.	Network
		c.	Relational
		d.	Theoretical
		d.	Theoretical


Question 16	Object-oriented databases were not initially commercially successful for which of the following reasons?

Correct
1.00 points out	Select one:
of 1.00		a.	They had high transition costs
		a.	They had high transition costs
		b.	They had overly lengthy queries
		c.	They were difficult to understand
		d.	They were incompatible with many applications


Question 17	Which of the following statements best describes object-relational databases?

Incorrect
0.00 points out	Select one:
of 1.00		a.	They have little vendor support
		a.	They have little vendor support
		b.	They integrate multiple paradigms
		c.	They cannot be easily implemented
		c.	They cannot be easily implemented
		d.	They integrate incompatible paradigms


Question 18	A non-relational data model based on binary trees is which of the following models?

Incorrect
0.00 points out	Select one:
of 1.00		a.	Entity
		a.	Entity
		b.	Hierarchical
		b.	Hierarchical
		c.	Network
		d.	Object


Question 19	Which of the following is an example of a use of an E-R diagram?

Correct
1.00 points out	Select one:
of 1.00		a.	A model of a database
		a.	A model of a database
		b.	A design of a database
		c.	A diagram of a database
		c.	A diagram of a database
		d.	A specification of database requirements

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Question 20	In this figure, what is TextBook an example of?
	In this figure, what is TextBook an example of?
Incorrect
0.00 points out
of 1.00

Select one:

a. Primary key

b. Ccomposite key

c. Multivalued attribute

d. Single-valued attribute

Question 21	In this figure, what is Address an example of?
	In this figure, what is Address an example of?
Incorrect
0.00 points out
of 1.00

Select one:

a. Candidate key

b. Primary attribute

c. Composite attribute

d. Multivalued attribute

5 of 15

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Question 22	Which of the following is true of the ER diagram in the figure below?

Incorrect
0.00 points out
of 1.00

Select one:

a. An employee can work for many departments

b. An employee can work for one department and a department can only have one employee

c. An employee can work for one department and a department can have one or more employees

d. An employee can work for one department only and a department does not have to have employees

Question 23

Incorrect

0.00 points out of 1.00

Question 24

Incorrect

0.00 points out of 1.00

Which of the following can we use to indicate whether an entity instance is mandatory?

Select one:

a. Cardinality

b. Optionality

c. Disjointedness

d. Referential integrity

Your answer is incorrect.

You have an application domain that consists of Cities, Towns, and Neighborhoods. A City has a name, zip code, state, and a country. A Town has a name, zip code, state, and country. A Neighborhood has a name, coordinate, and population. Using a relational model, wha Students, Courses, and Sections called?

Select one:

a. Attributes

b. Constraints

c. Entities

d. Relations

Your answer is incorrect.

6 of 15

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Question 25

Incorrect

0.00 points out of 1.00

This figure shows an ER diagram that contains a many to many relationship and four possible ways to map the diagram to a set of relations. Which mapping is correct?

Select one:

a.

Your answer is incorrect.

7 of 15

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Question 26	This figure shows an ER diagram that contains a one-to-one relationship and four possible ways to map the diagram to a set of relations. Which is the correct solution to mapping this ER diagram to a set of relations?

Incorrect
0.00 points out
of 1.00

Select one:

a.

Question 27

Correct

1.00 points out of 1.00

Your answer is incorrect.

Which of the following is an additional constraint that is added by users or database administrators?

Select one:

a. Entity integrity

b. Domain integrity

c. Semantic integrity

d. Referential integrity

Question 28	Which of the following should we always do when preparing to map an ER diagram to relations?

Incorrect
0.00 points out	Select one:
of 1.00		a. Normalize the ERD until no more normalization can be done

		b. Check that the DBMS can interpret the constraints in the ERD
		c. Make sure that we have simplified the ERD as much as possible

		d. Make sure that our ERD has only one entity and one relationship

8 of 15

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student.sid = course.sid

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Question 29

Incorrect

0.00 points out of 1.00

Which is the correct expression to find all students registered for CS403?

Select one:

a. σcourse_id="CS403" (course)

b. σdescription="CS403" (course)

c. σcourse_id = "CS403" (registration)

d. σdescription="CS403" (registration)

Question 30

Incorrect

0.00 points out of 1.00

In relational algebra, how would one select just the name from the student relation?

Select one:

a. Π (Student)

b. Π (Course)

c. ΠName (Student)

d. σname (Student)

Question 31

Correct

1.00 points out of 1.00

Question 32

Incorrect

0.00 points out of 1.00

Assuming that we have an additional relation called staff which is union compatible with faculty, what will the following operation result in?

Πname (Staff Instructor)

Select one:

a. No rows being printed

b. The cartesian product of instructor and staff

c. All rows of instructor being added to all rows of staff

d. The name of all rows which are in both staff and instructor

What would the following operation produce for output?

πdescription,name((course course.courseid = registration.courseid registration) sid = student.sid student)

Select one:

a. All course descriptions and names of all students

b. Registered students and all the course descriptions

c. All student names and all courses that are registered

d. Registered students and descriptions of their courses

Question 33

Correct

1.00 points out of 1.00

Which of the following is this operation an example of?

Student Course

Select one:

a. An equijoin

b. A hash join

c. A theta join

d. Aa natural join

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Question 34	A relation is considered to be in Boyce-Codd normal form if and only if which of the following applies?

Incorrect
0.00 points out	Select one:
of 1.00		a. It is in fourth normal form
		a. It is in fourth normal form
		b. There are transitive dependencies
		c. Every determinant is a candidate key
		d. There are some partial functional dependencies
		d. There are some partial functional dependencies


Question 35	What is the highest normal form that all relations in the diagram are in?

Incorrect
0.00 points out
of 1.00

Select one:

a. First normal form

b. Third normal form

c. Fourth normal form

d. Boyce-Codd normal form

Question 36	Which of the following terms describes one attribute (or field) that determines the value of another attribute?

Incorrect
0.00 points out	Select one:
of 1.00		a.	Foreign key
		a.	Foreign key
		b.	Primary key
		b.	Primary key
		c.	Independent key
		d.	Functional dependency

Question 37

Incorrect

0.00 points out of 1.00

Consider the following database table:

PartNo	Description	CustID	Name	QuantityOrdered

2361	Pens	7810	J. Smith	22

2371	Paper Clips	7810	J. Smith	1000

2914	Pens	7914	K. Jones	900

If J. Smith changes her last name to Klein, we would have to update multiple rows in the table. Which of the following is this an example of?

Select one:

a. A hash anomaly

b. A deletion anomaly

c. An update anomaly

d. An insertion anomaly

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