Database - The Relational Model and Normalization MCQs Part

1. Every time attribute A appears, it is matched with the same value of attribute B, but not the same value of attribute C. Therefore, it is true that:

A.
A → B.
B.
A → C.
C.
A → (B,C).
D.
(B,C) → A.

 Answer Option A

2. The different classes of relations created by the technique for preventing modification anomalies are called:

A.
normal forms.
B.
referential integrity constraints.
C.
functional dependencies.
D.
None of the above is correct.

 Answer Option A

3. A relation is in this form if it is in BCNF and has no multivalued dependencies:

A.
second normal form.
B.
third normal form.
C.
fourth normal form.
D.
domain/key normal form.

 Answer Option C

4. Row is synonymous with the term:

A.
record.
B.
relation.
C.
column.
D.
field.

 Answer Option A

5. The primary key is selected from the:

A.
composite keys.
B.
determinants.
C.
candidate keys.
D.
foreign keys.

 Answer Option C

6. Which of the following is a group of one or more attributes that uniquely identifies a row?

A. Key
B. Determinant
C. Tuple
D. Relation

 Answer Option A

7. When the values in one or more attributes being used as a foreign key must exist in another set of one or more attributes in another table, we have created a(n):

A. transitive dependency.
B. insertion anomaly.
C. referential integrity constraint.
D. normal form.

 Answer Option C

8. A relation is considered a:

A. Column.
B. one-dimensional table.
C. two-dimensional table.
D. three-dimensional table.

 Answer Option C

9. In the relational model, relationships between relations or tables are created by using:

A. composite keys.
B. determinants.
C. candidate keys.
D. foreign keys.

 Answer Option D

10. A functional dependency is a relationship between or among:

A. tables.
B. rows.
C. relations.
D. attributes.

 Answer Option D

11. Table is synonymous with the term:

A. record.
B. relation.
C. column.
D. field.

 Answer Option B

12. Which of the following is not a restriction for a table to be a relation?

A. The cells of the table must contain a single value.
B. All of the entries in any column must be of the same kind.
C. The columns must be ordered.
D. No two rows in a table may be identical.

 Answer Option C

13. For some relations, changing the data can have undesirable consequences called:

A. referential integrity constraints.
B. modification anomalies.
C. normal forms.
D. transitive dependencies.

 Answer Option B

14. A key:

A. must always be composed of two or more columns.
B. can only be one column.
C. identifies a row.
D. identifies a column.

 Answer Option C

15. An attribute is a(n):

A. column of a table.
B. two dimensional table.
C. row of a table.
D. key of a table.

 Answer Option A

16. A relation in this form is free of all modification anomalies.

A. First normal form
B. Second normal form
C. Third normal form
D. Domain/key normal form

 Answer Option D

17. If attributes A and B determine attribute C, then it is also true that:

A. A → C.
B. B → C.
C. (A,B) is a composite determinant.
D. C is a determinant.

 Answer Option C

18. A tuple is a(n):

A. column of a table.
B. two dimensional table.
C. row of a table.
D. key of a table.

 Answer Option C

19. If attribute A determines both attributes B and C, then it is also true that:

A. A → B.
B. B → A.
C. C → A.
D. (B,C) → A.

 Answer Option A

20. One solution to the multivalued dependency constraint problem is to:

A. split the relation into two relations, each with a single theme.
B. change the theme.
C. create a new theme.
D. add a composite key.

 Answer Option A

6. Which of the following is a group of one or more attributes that uniquely identifies a row?

A. Key
B. Determinant
C. Tuple
D. Relation

 Answer Option A

7. When the values in one or more attributes being used as a foreign key must exist in another set of one or more attributes in another table, we have created a(n):

A. transitive dependency.
B. insertion anomaly.
C. referential integrity constraint.
D. normal form.

 Answer Option C

8. A relation is considered a:

A. Column.
B. one-dimensional table.
C. two-dimensional table.
D. three-dimensional table.

 Answer Option C

9. In the relational model, relationships between relations or tables are created by using:

A. composite keys.
B. determinants.
C. candidate keys.
D. foreign keys.

 Answer Option D

10. A functional dependency is a relationship between or among:

A. tables.
B. rows.
C. relations.
D. attributes.

 Answer Option D

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