DBMS Basic

Attribute that can uniquely identify the tuples in

a relation is called _________

• Key

• Primary key

• Candidate key

• Alternate Key

An attribute which can uniquely identify tuples of the

table but is not defined as the primary key of the table.

• Key

• Composite key

• Candidate key

• Alternate Key

Special value that is stored when actual data value is

unknown for an attribute.

• Key

• NULL

• TUPLE

• DATA

Do foreign keys are allowed to have NULL values?

• Yes

• No

• Maybe

• None of the given

The Number of Tuples in a relation is known as ___________

• Degree

• Cardinality

• Attribute

• Primary key

__________ means same data are duplicated in

different places (files).

• Isolation

• Inconsistency

• Redundancy

• Dependence

__________ occurs when the same data maintained

in different places do not match

• Isolation

• Inconsistency

• Redundancy

• Dependence

________ is used to add certain restrictions or limitations on

the type of data that can be inserted in one or more

columns of a table.

• Rules

• Constraint

• Keys

• NULL

Which query is used to show table structure or schema which is the state

of the table is empty?

• Select

• Desc

• Show database

• Show tables

Which query is used to show the state or snapshot of the database

at any given time which is also known as a database instance.

• Select

• Desc

• Show database

• Show tables