Theory of Database Quiz 7 BSIT2B

1. It is defined as the process of applying a series of techniques and rules to a database in order to reduce data redundancy

Normalization

Normal form

Projection

Normalization is the process of organizing a database to eliminate redundancy and improve data integrity. By applying a series of techniques and rules, such as breaking down data into smaller tables and establishing relationships between them, normalization ensures that each piece of data is stored in only one place. This helps to minimize data duplication and inconsistencies, making the database more efficient and reliable. Therefore, normalization is the correct answer to the given question.

Explanation

Normalization is the process of organizing a database to eliminate redundancy and improve data integrity. By applying a series of techniques and rules, such as breaking down data into smaller tables and establishing relationships between them, normalization ensures that each piece of data is stored in only one place. This helps to minimize data duplication and inconsistencies, making the database more efficient and reliable. Therefore, normalization is the correct answer to the given question.

2. It is a normal form that states that all underlying simple domains contain atomic values only.

3NF or Third Normal Form

2NF or second normal form

1NF or First normal form

Normalization

The given correct answer is 1NF or First normal form. First normal form states that all underlying simple domains contain atomic values only. This means that each attribute in a relation should contain only a single value and should not be multivalued or contain any composite or derived values.

Explanation

The given correct answer is 1NF or First normal form. First normal form states that all underlying simple domains contain atomic values only. This means that each attribute in a relation should contain only a single value and should not be multivalued or contain any composite or derived values.

3. It is a normal form if and only if it is in 2NF and every non-key attribute is nontransitively dependent on the primary key

3NF or Third Normal Form

2NF or second normal form

1NF or First normal form

Normalization

The given correct answer states that a relation is in third normal form (3NF) if and only if it is in second normal form (2NF) and every non-key attribute is nontransitively dependent on the primary key. This means that in a 3NF relation, there are no transitive dependencies between non-key attributes. Transitive dependencies occur when a non-key attribute depends on another non-key attribute, which in turn depends on the primary key. By eliminating transitive dependencies, a relation can be further normalized and achieve a higher level of data integrity and efficiency. Therefore, the correct answer is 3NF or Third Normal Form.

Explanation

The given correct answer states that a relation is in third normal form (3NF) if and only if it is in second normal form (2NF) and every non-key attribute is nontransitively dependent on the primary key. This means that in a 3NF relation, there are no transitive dependencies between non-key attributes. Transitive dependencies occur when a non-key attribute depends on another non-key attribute, which in turn depends on the primary key. By eliminating transitive dependencies, a relation can be further normalized and achieve a higher level of data integrity and efficiency. Therefore, the correct answer is 3NF or Third Normal Form.

4. It is defined as any attribute that does not participate in the primary key of the relation concerned

Key attribute

Mutual independence

Non-key attribute

Determinant

A non-key attribute is defined as any attribute that does not participate in the primary key of the relation concerned. In other words, it is not used to uniquely identify a record in the relation. Non-key attributes can provide additional information about the record but are not essential for identifying it.

Explanation

A non-key attribute is defined as any attribute that does not participate in the primary key of the relation concerned. In other words, it is not used to uniquely identify a record in the relation. Non-key attributes can provide additional information about the record but are not essential for identifying it.

5. It is a description of the rules that a database at a certain level of normalization must follow

Normalization

Normal form

Projection

The correct answer is "normal form". In the context of databases, normalization refers to the process of organizing data in a database to eliminate redundancy and improve efficiency. Normal forms are a set of rules that a database must follow in order to be considered normalized. Each normal form has specific requirements that must be met, and they are designated by numbers (e.g., first normal form, second normal form, etc.). Therefore, the given answer is explaining that the correct answer is referring to the rules that a database at a certain level of normalization must follow.

Explanation

The correct answer is "normal form". In the context of databases, normalization refers to the process of organizing data in a database to eliminate redundancy and improve efficiency. Normal forms are a set of rules that a database must follow in order to be considered normalized. Each normal form has specific requirements that must be met, and they are designated by numbers (e.g., first normal form, second normal form, etc.). Therefore, the given answer is explaining that the correct answer is referring to the rules that a database at a certain level of normalization must follow.

6. It is a normal form that states that every nonkey attribute is fully dependent on the primary key.

3NF or Third Normal Form

2NF or second normal form

1NF or First normal form

Normalization

The given correct answer is 2NF or second normal form. Second normal form states that every nonkey attribute must be fully dependent on the primary key. This means that no partial dependencies are allowed, and all nonkey attributes should depend on the entire primary key, not just a part of it.

Explanation

The given correct answer is 2NF or second normal form. Second normal form states that every nonkey attribute must be fully dependent on the primary key. This means that no partial dependencies are allowed, and all nonkey attributes should depend on the entire primary key, not just a part of it.

7. If a table is in third normal form

It is also in Boyce-Codd normal form

It contains non-atomic attributes

It does not contain any transitive dependencies

It contains attributes that are not fully functionally dependent on the key

If a table is in third normal form, it means that it meets the requirements of the first, second, and third normal forms. One of the requirements of the third normal form is that it does not contain any transitive dependencies. Transitive dependencies occur when an attribute depends on another attribute, which in turn depends on the primary key. By not having any transitive dependencies, the table is considered to be in third normal form.

Explanation

If a table is in third normal form, it means that it meets the requirements of the first, second, and third normal forms. One of the requirements of the third normal form is that it does not contain any transitive dependencies. Transitive dependencies occur when an attribute depends on another attribute, which in turn depends on the primary key. By not having any transitive dependencies, the table is considered to be in third normal form.

8. It is a normal form if and only if every determinant is a candidate key

3NF or Third Normal Form

2NF or second normal form

1NF or First normal form

BCNF or Boyce-Codd normal form

BCNF or Boyce-Codd normal form is the correct answer because it is a higher level of normalization compared to 1NF, 2NF, and 3NF. In BCNF, every determinant (attribute or set of attributes that uniquely determines other attributes) must be a candidate key. This means that there should be no non-trivial functional dependencies where a determinant is not a candidate key. BCNF ensures that there are no redundancy and anomalies in the database design, making it a more optimal and efficient form.

Explanation

BCNF or Boyce-Codd normal form is the correct answer because it is a higher level of normalization compared to 1NF, 2NF, and 3NF. In BCNF, every determinant (attribute or set of attributes that uniquely determines other attributes) must be a candidate key. This means that there should be no non-trivial functional dependencies where a determinant is not a candidate key. BCNF ensures that there are no redundancy and anomalies in the database design, making it a more optimal and efficient form.

9. This condition exists among attributes within a relation if none of them are functionally dependent on any combination of the others

Key attribute

Non-key attribute

Determinant

Mutual independence

Mutual independence refers to a condition in which none of the attributes within a relation are functionally dependent on any combination of the others. In other words, each attribute in the relation is independent and does not rely on any other attribute for its value. This ensures that there are no relationships or dependencies between the attributes, making them mutually independent of each other.

Explanation

Mutual independence refers to a condition in which none of the attributes within a relation are functionally dependent on any combination of the others. In other words, each attribute in the relation is independent and does not rely on any other attribute for its value. This ensures that there are no relationships or dependencies between the attributes, making them mutually independent of each other.

10. If a table is in second normal form.

It is also in first normal form

It is also in third normal form

It does not contain any transitive dependencies

It contains attributes that are not fully functionally dependent on the key

If a table is in second normal form, it means that it is already in first normal form because second normal form builds upon the requirements of first normal form. Therefore, the correct answer is that the table is also in first normal form.

Explanation

If a table is in second normal form, it means that it is already in first normal form because second normal form builds upon the requirements of first normal form. Therefore, the correct answer is that the table is also in first normal form.

Theory Of Database Quiz 7 Bsit2b