Explore topic-wise MCQs in Database.

This section includes 30 Mcqs, each offering curated multiple-choice questions to sharpen your Database knowledge and support exam preparation. Choose a topic below to get started.

1.

In a 1:M relationship, the primary key on the one side migrates to the many side to become the foreign key on the many side.

A. 1
B.
Answer» B.
Discussion
2.

If a relation is in third normal form, it does not need to be in second normal form.

A. 1
B.
Answer» C.
Discussion
3.

A synonym is two or more attributes that have different names but the same meaning.

A. 1
B.
Answer» B.
Discussion
4.

Normalization is a formal process for deciding which attributes should be grouped together in a relation.

A. 1
B.
Answer» B.
Discussion
5.

The primary key in a relation does not need to be underlined.

A. 1
B.
Answer» C.
Discussion
6.

The primary key of the new relation in a many-to-many relationship is a composite key comprised of the primary keys of each of the binary entities.

A. 1
B.
Answer» B.
Discussion
7.

A foreign key may be null and still adhere to the referential integrity constraint.

A. 1
B.
Answer» B.
Discussion
8.

Well-structured relations encourage anomalies of data.

A. 1
B.
Answer» C.
Discussion
9.

When mapping a binary many-to-many relationship into a relation which of the following is true?

A. One relation is created.
B. Two relations are created.
C. Three relations are created.
D. Four relations are created.
Answer» D. Four relations are created.
Discussion
10.

If no multivalued attributes exist in a relation, then the relation is in what normal form?

A. First normal form
B. Second normal form
C. Third normal form
D. Fourth normal form
Answer» B. Second normal form
Discussion
11.

A primary key is which of the following?

A. Any attribute
B. An attribute that uniquely identifies each row
C. An attribute that uniquely identifies each column
D. A derived attribute
Answer» C. An attribute that uniquely identifies each column
Discussion
12.

A null value is assigned when no other value applies.

A. 1
B.
C. 1
D.
Answer» B.
Discussion
13.

When mapping a regular entity into a relation which of the following is true?

A. One relation is created.
B. Two relations are created.
C. Three relations are created.
D. Four relations are created.
Answer» B. Two relations are created.
Discussion
14.

When mapping a supertype/subtype relationship which of the following is true?

A. The supertype primary key is assigned to each subtype.
B. The subtype primary key is assigned to each supertype.
C. There is no link between the supertype/subtype entities.
D. There is no primary key/foreign key relationship between a supertype/subtype.
Answer» B. The subtype primary key is assigned to each supertype.
Discussion
15.

The relational model consists of:

A. data in the form of tables.
B. data redundancy.
C. operations using non-SQL languages.
D. unorganized data.
Answer» B. data redundancy.
Discussion
16.

Weak entities do not get mapped into a relation.

A. 1
B.
Answer» C.
Discussion
17.

A primary key may be null.

A. 1
B.
Answer» C.
Discussion
18.

When mapping a ternary relationship with an associative entity into a relation which of the following is true?

A. One relation is created.
B. Two relations are created.
C. Three relations are created.
D. Four relations are created.
Answer» E.
Discussion
19.

Relations are:

A. two-dimensional tables.
B. three-dimensional tables.
C. four-dimensional tables.
D. five-dimensional tables.
Answer» B. three-dimensional tables.
Discussion
20.

A relation is a two-dimensional table.

A. 1
B.
Answer» B.
Discussion
21.

A composite attribute does not get mapped into a relation.

A. 1
B.
Answer» B.
Discussion
22.

A candidate key must uniquely identify each row.

A. 1
B.
C. 1
D.
Answer» B.
Discussion
23.

When mapping a multivalued attribute into a relation which of the following is true?

A. One relation is created.
B. Two relations are created.
C. Three relations are created.
D. Four relations are created.
Answer» C. Three relations are created.
Discussion
24.

An enterprise key is a primary key whose value is unique for a given relation.

A. 1
B.
C. 1
D.
Answer» C. 1
Discussion
25.

A transitive dependency is which of the following?

A. A functional dependency between two or more key attributes.
B. A functional dependency between two or more nonkey attributes.
C. A relation that is in first normal form.
D. A relation that is in second normal form.
Answer» C. A relation that is in first normal form.
Discussion
26.

When mapping a many-to-many unary relationship into a relation which of the following is true?

A. One relation is created.
B. Two relations are created.
C. Three relations are created.
D. Four relations are created.
Answer» C. Three relations are created.
Discussion
27.

If no multivalued attributes exist and no partial dependencies exist in a relation, then the relation is in what normal form?

A. First normal form
B. Second normal form
C. Third normal form
D. Fourth normal form
Answer» C. Third normal form
Discussion
28.

A foreign key is which of the following?

A. Any attribute
B. The same thing as a primary key
C. An attribute that serves as the primary key of another relation
D. An attribute that serves no purpose
Answer» D. An attribute that serves no purpose
Discussion
29.

A relation has which of the following properties?

A. Each row is not unique.
B. Attributes can have the same name within a given table.
C. Each relation has a unique name.
D. The order of the columns is significant.
Answer» D. The order of the columns is significant.
Discussion
30.

The entity integrity rule states that:

A. no primary key attribute may be null.
B. no primary key can be composite.
C. no primary key may be unique.
D. no primary key may be equal to a value in a foreign key.
Answer» B. no primary key can be composite.
Discussion