Database Management Systems (3130703) MCQs

MCQs of Relational Query Languages

Showing 11 to 20 out of 40 Questions
11.

Which of the following key is an attribute in relation of a database that serves as the primary key of another relation in the same database?

(a)

Composite Key

(b)

Foreign Key

(c)

Primary Key

(d)

Unique Key

Answer:

Option (b)

12.

A primary key that consists of more than one field is called a _____________

(a)

Composite key

(b)

Secondary key

(c)

Group key

(d)

Joined key

Answer:

Option (a)

13.

A foreign key must ________

(a)

Be numeric

(b)

Be unique

(c)

Be defined in all tables within the database

(d)

Match the field value of a primary key in a related table

Answer:

Option (d)

14.

Cartesian product in relational algebra is __________

(a)

a unary operator

(b)

a binary operator

(c)

a ternary operator

(d)

not defined

Answer:

Option (b)

15.

Relational Algebra is _____________

(a)

Data Definition Language

(b)

Meta Language

(c)

Procedural Query Language

(d)

Binary Language

Answer:

Option (c)

16.

Key to represent relationship between tables is called __________________

(a)

Primary key

(b)

Secondary Key

(c)

Foreign Key

(d)

Alternate Key

Answer:

Option (c)

17.

_______ produces the relation that has attributes of R1 and R2

(a)

Cartesian product

(b)

Difference

(c)

Intersection

(d)

Product

Answer:

Option (a)

18.

Which of the following operation is used if we are interested in only certain columns of a table?

(a)

PROJECTION

(b)

SELECTION

(c)

UNION

(d)

JOIN

Answer:

Option (a)

19.

Which of the following operations need the participating relations to be union compatible?

(a)

UNION

(b)

INTERSECTION

(c)

DIFFERENCE

(d)

UNION, INTERSECTION, DIFFERENCE

Answer:

Option (d)

20.

The result of the UNION operation between R1 and R2 is a relation that includes

(a)

all the tuples of R1

(b)

all the tuples of R2

(c)

all the tuples of R1 but not in R2

(d)

all the tuples of R1 and R2 which have common columns

Answer:

Option (d)

Showing 11 to 20 out of 40 Questions