Database - Logical Database Design MCQs Part

1. 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 Option A

2. 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 Option B

3. 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 Option B

4. 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 Option C

5. 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 Option B

6. 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 Option B

7. 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 Option A

8. 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 Option B

9. 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 Option A

10. 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 Option C

11. 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 Option C

12. 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 Option D

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 Option A

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 Option A

15. Relations are:

A. two-dimensional tables.
B. three-dimensional tables.
C. four-dimensional tables.
D. five-dimensional tables.

 Answer Option A

6. 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 Option B

7. 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 Option A

8. 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 Option B

9. 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 Option A

10. 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 Option C

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