Database Management System MCQ– Keys

tekkifly July 07, 2020

1. Which one of the following is a set of one or more attributes taken collectively to uniquely identify a record?

Super key
Candidate key
Sub key
Foreign key

2. Consider attributes ID, PLACE and NAME. Which one of this can be considered as a super key?

ID
PLACE
NAME
NONE

3. The subset of a super key is a candidate key under what condition?

Each subset is a super key
All subsets are super keys
No proper subset is a super key
Subset is a super key

4. A _____ is a property of the entire relation, rather than of the individual tuples in which each tuple is unique.

Key
Attribute
Rows
Fields

5. Which one of the following attribute can be taken as a primary key?

Id
Name
Street
Department

6. Which one of the following cannot be taken as a primary key?

Dept_id
Register number
Id
Street

7. An attribute in a relation is a foreign key if the _______ key from one relation is used as an attribute in that relation.

Primary
Candidate
Sub
Super

8. The relation with the attribute which is the primary key is referenced in another relation. The relation which has the attribute as a primary key is called

Referenced relation
Referential relation
Referencing relation
Referred relation

9. The ______ is the one in which the primary key of one relation is used as a normal attribute in another relation.

Referenced relation
Referential relation
Referred relation
Referencing relation

10. A _________ integrity constraint requires that the values appearing in specified attributes of any tuple in the referencing relation also appear in specified attributes of at least one tuple in the referenced relation.