Question 1

If a 1:M relationship is optional on both sides,which of the following is true?

Accepted Answer

A) The resulting foreign key can have null (empty)values 
B) The resulting foreign key cannot have null (empty)values 
C) The resulting foreign key must have null (empty)values 
D) No foreign key is created as a result of mapping such a relationship

Question 2

ABC RETAILER
Observe the ER diagram for the ABC Retailer:

This ER diagram will be used for the following questions citing ABC Retailer ER Diagram. 
-How many foreign keys will the relational schema mapped from the ABC Retailer ER diagram have?

Accepted Answer

A) 0 
B) 1 
C) 2 
D) 3

Question 3

CENTRAL SCHOOL LIBRARY
Observe the ER diagram for the CENTRAL SCHOOL LIBRARY
 
-How many columns will the relation COPY have in the relational schema mapped from the Central School Library ER diagram?

Accepted Answer

A) 2 
B) 3 
C) 4 
D) 5

Question 4

Two columns of a relational table can have the same names.

Accepted Answer

A) True 
 B)False

Question 5

CENTRAL SCHOOL LIBRARY
Observe the ER diagram for the CENTRAL SCHOOL LIBRARY
 
-How many bridge tables will the relational schema mapped from the Central School Library ER diagram have?

Accepted Answer

A) 0 
B) 1 
C) 2 
D) 3

Question 6

An entity and its 1:M unary relationship are mapped as one relation.

Accepted Answer

A) True 
 B)False

Question 7

ABC RETAILER
Observe the ER diagram for the ABC Retailer:

This ER diagram will be used for the following questions citing ABC Retailer ER Diagram. 
-How many optional columns will the relational schema mapped from the ABC Retailer ER diagram have?

Accepted Answer

A) 0 
B) 1 
C) 2 
D) 3

Question 8

EAGLERUN TRUCKING DISPATCHER
Observe the ER diagram for the Eaglerun Trucking
 Dispatcher:

This ER diagram will be used for the following questions citing Eaglerun Trucking Dispatcher ER Diagram.

-How many bridge tables will the relational schema mapped from the Eaglerun Trucking Dispatcher ER diagram have?

Accepted Answer

A) 0 
B) 1 
C) 2 
D) 3

Question 9

ZYX COMPANY
Observe the ER diagram for the ZYX COMPANY:
 
This ER diagram will be used for the following questions citing ZYX Company ER Diagram.
-During mapping of the ZYX Company ERD into a relational schema,attribute EmpID from the ZYX Company ER diagram will be mapped as a column of the relation EMPLOYEE.

Accepted Answer

A) True 
 B)False

Question 10

ZYX COMPANY
Observe the ER diagram for the ZYX COMPANY:
 
This ER diagram will be used for the following questions citing ZYX Company ER Diagram.
-As a result of mapping the ZYX Company ERD into a relational schema,primary key of the relation EMPLOYEE will be referred to by a foreign key in the relation CUSTOMER.

Accepted Answer

A) True 
 B)False

Question 11

ABC RETAILER
Observe the ER diagram for the ABC Retailer:

This ER diagram will be used for the following questions citing ABC Retailer ER Diagram. 
-How many columns will the relation PROMOTION have in the relational schema mapped from the ABC Retailer ER diagram?

Accepted Answer

A) 2 
B) 3 
C) 4 
D) 5

Question 12

Two columns of two different tables in the same relational database can have the same names.

Accepted Answer

A) True 
 B)False

Question 13

Use an example to illustrate how M:N relationships and associative entities are mapped in the same way.

Accepted Answer

The answer of Use an example to illustrate how M:N...

Question 14

If an M:N relationship is mandatory on both sides,and if both relations resulting from the entities involved in the relationship each have 3 records,then the resulting bridge relation cannot have less than ________ records.

Accepted Answer

A) 0 
B) 1 
C) 3 
D) 9

Question 15

How many columns will a relation resulting from mapping the Entity Y have?

Accepted Answer

A) 2 
B) 3 
C) 4 
D) 5

Question 16

If a 1:M relationship is mandatory on both sides,and if the table resulting from the 1 side has 3 records,then the table resulting from the M side CANNOT have less than ________ records.

Accepted Answer

A) 0 
B) 1 
C) 2 
D) 3

Question 17

ABC RETAILER
Observe the ER diagram for the ABC Retailer:

This ER diagram will be used for the following questions citing ABC Retailer ER Diagram. 
-How many tables will the relational schema mapped from the ABC Retailer ER diagram have?

Accepted Answer

A) 2 
B) 3 
C) 4 
D) 5

Question 18

Two columns of a relational table can have the same values.

Accepted Answer

A) True 
 B)False

Question 19

Within one relation,two rows can be identical.

Accepted Answer

A) True 
 B)False

Question 20

A relation resulting from a weak entity has a non-composite primary key when the identifying relationship is:

Accepted Answer

A) Optional on both sides 
B) 1:1 
C) 1:M 
D) M:N

Exam 3: Relational Database Modeling

If a 1:M relationship is optional on both sides,which of the following is true?

ABC RETAILER Observe the ER diagram for the ABC Retailer: This ER diagram will be used for the following questions citing ABC Retailer ER Diagram. -How many foreign keys will the relational schema mapped from the ABC Retailer ER diagram have?

CENTRAL SCHOOL LIBRARY Observe the ER diagram for the CENTRAL SCHOOL LIBRARY -How many columns will the relation COPY have in the relational schema mapped from the Central School Library ER diagram?

Two columns of a relational table can have the same names.

CENTRAL SCHOOL LIBRARY Observe the ER diagram for the CENTRAL SCHOOL LIBRARY -How many bridge tables will the relational schema mapped from the Central School Library ER diagram have?

An entity and its 1:M unary relationship are mapped as one relation.

ABC RETAILER Observe the ER diagram for the ABC Retailer: This ER diagram will be used for the following questions citing ABC Retailer ER Diagram. -How many optional columns will the relational schema mapped from the ABC Retailer ER diagram have?

ABC RETAILER Observe the ER diagram for the ABC Retailer: This ER diagram will be used for the following questions citing ABC Retailer ER Diagram. -How many columns will the relation PROMOTION have in the relational schema mapped from the ABC Retailer ER diagram?

Two columns of two different tables in the same relational database can have the same names.

Use an example to illustrate how M:N relationships and associative entities are mapped in the same way.

If an M:N relationship is mandatory on both sides,and if both relations resulting from the entities involved in the relationship each have 3 records,then the resulting bridge relation cannot have less than ________ records.

How many columns will a relation resulting from mapping the Entity Y have?

If a 1:M relationship is mandatory on both sides,and if the table resulting from the 1 side has 3 records,then the table resulting from the M side CANNOT have less than ________ records.

ABC RETAILER Observe the ER diagram for the ABC Retailer: This ER diagram will be used for the following questions citing ABC Retailer ER Diagram. -How many tables will the relational schema mapped from the ABC Retailer ER diagram have?

Two columns of a relational table can have the same values.

Within one relation,two rows can be identical.

A relation resulting from a weak entity has a non-composite primary key when the identifying relationship is: