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CS403: Certiﬁcate Final Exam: Attempt review | Saylor Academy

https://learn.saylor.org/mod/quiz/review.php?attempt=1608501&cmid=23178&showall=1

Back to 'Certificate Final Exam\'

Started on	Wednesday, April 27, 2022, 11:08 AM

State	Finished

Completed on	Wednesday, April 27, 2022, 11:58 AM

Time taken	50 mins 56 secs

Points	47.00/50.00

Grade	9.40 out of 10.00 (94%)

Question 1

Correct

1.00 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?

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

Question 3

Correct

1.00 points out of 1.00

Which of the following is data?

Select one: a. 32

b. I am 32

c. It is 32 degrees. d. It is 32 outside.

Question 4	Which of the following sets of terms describes the data in a database?

Correct
1.00 points out	Select one:
of 1.00	a.	integrated and shared
	a.	integrated and shared
	b.	redundant and accurate
	c.	functional and redundant
	d.	transactional and unconstrained

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Question 5	Which of the following best describes a database?
	Which of the following best describes a database?
Correct
1.00 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


Question 6	Which of the following describes a DBMS?
	Which of the following describes a DBMS?
Correct
1.00 points out	Select one:
of 1.00		a.	A part of a database
		a.	A part of a database
		b.	A database application
		c.	An interface between applications
		d.	An interface between a database and users of the database


Question 7	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 8	Which kind of database corresponds to 'graph'?
	Which kind of database corresponds to 'graph'?
Incorrect
0.00 points out	Select one:
of 1.00		a.	Network
		a.	Network
		b.	Relational
		b.	Relational
		c.	Hierarchical
		d.	Object-oriented


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

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Question 10	Which view in the three-level database architecture offers a formal description of the data with no concern for how it will be stored?

Correct
1.00 points out	Select one:
of 1.00		a.	Conceptual
		a.	Conceptual
		b.	Data
		c.	External
		d.	Internal


Question 11	Which of the following describes the capability to change the physical schema of a database without having to rewrite application programs?

Correct
1.00 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


Question 12	Indices are useful for searching a database because they decrease which of the following?

Correct
1.00 points out	Select one:
of 1.00		a.	query complexity
		a.	query complexity
		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 13	What is commonly used to represent a relation?
	What is commonly used to represent a relation?
Correct
1.00 points out	Select one:
of 1.00		a.	an index
		a.	an index
		b.	a schema
		b.	a schema
		c.	a table
		d.	a view


Question 14	What are rules that are valid for information in a database called?

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

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Question 15	What did the predecessor to modern databases stored data in?

Correct
1.00 points out	Select one:
of 1.00		a.	Flat files
		a.	Flat files
		b.	Rough files
		c.	Magnetic tape
		d.	Punched cards


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?

Correct
1.00 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
		d.	They integrate incompatible paradigms


Question 18	If you were a database consultant tasked with recommending a data model for organizing book records for a library, which of the following types of database would you recommend?

Correct
1.00 points out	Select one:
of 1.00		a.	Hierarchical
		a.	Hierarchical
		b.	NoSQL
		b.	NoSQL
		c.	Object
		d.	Relational

Question 19

Correct

1.00 points out of 1.00

Which of the following statements describes the role of an E-R diagram in the development of a relational database?

Select one:

a. An E-R diagram is transformed into the database design.

b. An E-R diagram is transformed into the internal database.

c. An E-R diagram is transformed into the physical database.

d. An E-R diagram is used to represent the database requirements.

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Question 20	On an ER diagram, which shape is used to represent an entity?

Correct
1.00 points out	Select one:
of 1.00	a.	Circle
	a.	Circle
	b.	Diamond
	c.	Oval
	d.	Rectangle

Question 21	Which of the following is true of the ER diagram in the figure below?

Correct
1.00 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 22	What kind of relationship is this figure an example of?
	What kind of relationship is this figure an example of?
Correct
1.00 points out
of 1.00

Select one:

a. Binary

b. Singleton

c. Ternary d. Unary

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Question 23

Correct

1.00 points out of 1.00

Question 24

Correct

1.00 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 correct.

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, Students, Courses, and Sections called?

Select one:

a. Attributes

b. Constraints

c. Entities

d. Relations

Your answer is correct.

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Question 25

Correct

1.00 points out of 1.00

The diagram contains a unary entity with a one to many relationship. Which of the following best demonstrates a mapping of this relationship?

Select one:

c.

Your answer is correct.

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Question 26

Correct

1.00 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:

b.

Your answer is correct.

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Question 27	Which of the following statements about domain constraints is true?

Correct
1.00 points out	Select one:
of 1.00	a.	They cannot be used in most modern database systems
	a.	They cannot be used in most modern database systems
	b.	They ensure values entered into a table satisfy conditions
	c.	They can only check numeric values for arithmetic relations
	d.	They cannot always be implemented in some SQL implementations


Question 28	Which of the following is an additional constraint that is added by users or database administrators?

Correct
1.00 points out	Select one:
of 1.00	a.	Entity integrity
	a.	Entity integrity
	b.	Domain integrity
	c.	Semantic integrity
	d.	Referential integrity


Question 29	What is a tuple?
	What is a tuple?
Correct
1.00 points out	Select one:
of 1.00	a.	A field in a relation
	a.	A field in a relation
	b.	An index on a table
	c.	A way for a database to store tables
	d.	A collection of attributes of a relation

Question 30

Correct

1.00 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 31

Correct

1.00 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

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Question 32	Which of the following is Student Courses an example of?
	Which of the following is Student Courses an example of?
Correct
1.00 points out	Select one:
of 1.00	a.	A theta join
	a.	A theta join
	b.	An inner join
	c.	A natural join
	d.	A cartesian product

Question 33

Correct

1.00 points out of 1.00

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

Incorrect
0.00 points out
of 1.00
	Select one:
	Select one:
	a.	First normal form
	b.	Third normal form
	c.	Fourth normal form
	d.	Boyce-Codd normal form


Question 35	In what normal form is the relation in the figure?
	In what normal form is the relation in the figure?
Correct
1.00 points out
of 1.00
	Select one:
	Select one:
	a.	First normal form
	b.	Second normal form
	c.	Third normal form
	d.	Boyce-Codd normal form

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