Database Systems Test 1

b

Which statement is not a special case of foreign keys?

a. Multiple foreign keys referring to the same primary key

b. Foreign key referring to a foreign key in the same table

c. Composite foreign key referring to a composite primary key

d. Foreign key referring to a primary key in the same table

d

Which principle defines data independence?

a. Modification of indexes generates different results

b. Tuning query performance requires application modifications

c. Logical design maintains schema integrity

d. Physical design never affects query results

a

An entity named Stadium contains a primary key SeatNumber and a plural attribute SeatReservation which records spectator seat assignments. During implimentation, the plural attributes moved to a new table named ____

a. StadiumSeatReservation

b. StadiumSeatNumber

c. SeatReservationSeatNumber

d. SeatNumberSeatReservation

b

When creating an ER diagram, a dependency relationship is drawn with an arrow pointing to a ____ entity

a. independent

b. master

c. existence

d. functional

d

Boyce-Codd normal form provides an improvement over ____ normal form

a. second

b. first

c. fourth

d. third

a

What is the greatest number of instances of one entity that can relate to a single instance of another entity

a. Maximum

b. Minimum

c. Many-many

d. One

a

During database design, an entity with many optional attributes often becomes a(n) ____

a. Supertype

b. Master

c. Dependent

d. Independent

a

Optional attributes and relationships become columns that allow for ____ values

a. NULL

b. composite

c. artificial

d. subtype

a

Which two rules apply to primary keys?

a. Values must be unique and may not be NULL

b. Values can have duplicates and can be NULL

c. Values must be unique and can be NULL

d. Values can have duplicates and may not be NULL

b

The entity Book includes Paperback, Hardcover, and Digital books. The attribute ChapterCount applies to both PaperBack and HardCover but not Digital. Digital has a TextToSpeech attribute. Which entitiy type is Digital?

a. Supertype

b. Subtype

c. Similar

d. Master

d

Refer to the Teacher and Class tables. To maintain referential integrity, which foreign key action rejects the deletion of the row containing Rosa Lopez?
(There’s a table)

a. SET NULL

b. CASCADE

c. SET DEFAULT

d. RESTRICT

b

In the following ER diagram, what does ‘AlbumTitle’ represent?
ER diagram below:

records
Artist: ——→ Album:
ID _________ ID
Fname _____ AlbumYear
Lname _____ AlbumTitle

a. Relationship

b. Attribute

c. Key

d. Entity

d

Which role focuses on creating software that interacts with a database?

a. Designer

b. User

c. Administrator

d. Programmer

b

How are attributes documented in an entity-relationship diagram? (in ZyBook)

a. As a branching line from an entity

b. Within an entity rectangle

c. With a relationship line

d. As a shape connected to an entity

c

Refer to the Teacher and Class tables. Which foreign key action updates the TeacherID for the Web Development course to 45672 when Bryan McNeal’s Teacher ID is updated to 45672?
(TeacherID is a primary key in Teacher and a foreign key in Class)

a. SET DEFAULT

b. SET NULL

c. CASCADE

d. RESTRICT

a

Is DegreeCode a valid foreign key?

(o) DegreeCode: ———> (*) Code:
13 ____________________ 47
NULL _________________ 13
91 ____________________ 39
64 ____________________ 69

a. No

b. Yes

d

TaxiFleet: ——- OWNS ——— Taxi:
TaxiFleetID ______________ TaxiMedallionNumber
1(0) ____________ M(1)

What is the name of the new foreign key?

a. TaxiMedallionNumberTaxtFleetID

b. TaxiMediallionNumber

c. TaxiFleetIDTaxiMedallionNumber

d. TaxiFleetID

a

A person may not have a mobile phone. Determine the minimum for the attribute.
Entity Person, attribute MobilePhoneNumber

a. zero

b. one

b

With SET DEFAULT referential integrity, what happens if the row containing Slovenia is deleted from the country table
(There is a table connecting to a different table)

a. Delete is rejected

b. Row is deleted

c

Each title may be used for many books. Each book has at most one title. Determine the maxima for each Entity-Has-Attribute relationship
Entity Book, attribute Title

a. one-many

b. one-one

c. many-one

d. many-many

7000

Country:
Area1: _____________ Area2:
1897000 ___________ NULL
6000 ______________ 1000
NULL ______________ NULL
NULL ______________ 360000
NULL ______________ 67000

SELECT MAX(Area1 + Area2)
FROM Country;

Enter the result:

a

Assume the following rules:

A company has different divisions
A division may have many departments, and each department is in one division
The primary key of division is DivisionNumber
Each department has a required DepartmentName and DepartmentCode
DepartmentName is unique across all Departments
DepartmentCode is unique within a division but may be repeated for departments in different divisions

Select the best primary key for the department table

a. (DivisionNumber, DepartmentCode)

b. DepartmentName

c. DepartmentCode

d. (DivisionNumber, DepartmentName)

b

With RESTRICT referential integrity, what happens if the row containing Finland is denied from the Country table? (There is a table)

a. Row is deleted

b. Delete is rejected

100

Area:
100
NULL
NULL
93400
200

SELECT MIN(Area)
FROM Country;

Enter the result:

a

Column Names:

*ISO, CountryName, IndependenceDate, IndependenceYear

What columns depend on IndependenceDate?

a. IndependenceYear

b. ISO

c. CountryName

b

TaxiFleet: ——- OWNS ——— Taxi:

TaxiFleetID ______________ TaxiMedallionNumber

1(0) ____________________ M(1)

Are NULLs allowed in the foreign keys columns?

a. No

b. Yes

c

A book is not necessarily borrowed. A person may not have borrowed any books. Determine the relationship minima. Person-Borrows-Book

a. one-one

b. one-zero

c. zero-zero

d. zero-one

2257000

Country:

Area1: _____________ Area2:

1897000 ___________ NULL

6000 ______________ 1000

NULL ______________ NULL

NULL ______________ 360000

NULL ______________ 67000

SELECT MAX(Area1) + MAX(Area2)
FROM Country;

Enter the result:

b

Can Continent be a primary key of the Country table?

Continent:
Africa
NAmerica
Africa
Oceania
Africa

a. Yes

b. No

b

A streaming video service’s database is disabled due to a lightning strike. The IT department verifies that all database transactions performed before the lightning strike were saved on storage media

a. Prevent conflicts between concurrent transactions

b. Ensure transaction results are never lost

c. Transaction processed completely or not at all

c

Where are duplicate column names allowed?

a. Within a single table

b. Never

c. In different tables

b

Employee:
ID:
2538
5384
6381

A new employee can be added with ID 5384

a. True
b. False

c

How does a database administrator specify column names and data types?

a. With the Python language

b. In a special file managed by the database administrator

c. With the SQL language

b

What is the result of a relational operation?

a. A column

b. A table

c. A row