6 - Normalisation

What is the primary objective of normalization in a database?

• To enhance query performance

• To reduce data redundancy and improve data integrity

• To decrease the size of the database

• To remove primary keys

A table is in First Normal Form (1NF) if it:

• Has no repeating groups

• Contains only atomic values

• Has a primary key

• Both a and b

Which normal form eliminates partial dependency?

• 1NF

• 2NF

• 3NF

• 4NF

A table is in Second Normal Form (2NF) if:

• It is in 1NF and has no transitive dependencies

• It is in 1NF and has no partial dependencies

• It is in 1NF and all non-key attributes depend on the whole primary key

• Both b and c

Which of the following is true for Third Normal Form (3NF)?

• It is in 2NF and contains no transitive dependencies

• It is in 1NF and has no partial dependencies

• It only has atomic values

• It eliminates multi-valued dependencies

Transitive dependency means:

• Non-key attributes depend on other non-key attributes

• A foreign key depends on a primary key

• A candidate key depends on the primary key

• There is no dependency between columns

Which normal form eliminates transitive dependencies?

• 1NF

• 2NF

• 3NF

• 4NF

In which normal form should a table be if there are no repeating groups and all attributes are functionally dependent on the primary key?

• 1NF

• 2NF

• 3NF

• 4NF

Which of the following is a partial dependency?

• Non-key attributes are dependent on part of a composite key

• Non-key attributes are dependent on a non-key attribute

• Non-key attributes are dependent on a foreign key

• Non-key attributes are dependent on the whole primary key

What is required for a table to be in First Normal Form (1NF)?

• It must have a primary key

• It must not have any null values