Understanding Database Normalization

What is the definition of database normalization?

• Database normalization is the process of combining multiple databases into one.

• Database normalization refers to the encryption of sensitive data in a database.

• Database normalization is the process of organizing a database to reduce redundancy and improve data integrity.

• Database normalization is the method of backing up data to prevent loss.

What is the primary goal of normalization in databases?

• To simplify database queries and reduce performance.

• To increase data redundancy and decrease data integrity.

• The primary goal of normalization is to reduce data redundancy and improve data integrity.

• To enhance data visualization and reporting capabilities.

What does a table need to satisfy to be in First Normal Form (1NF)?

• A table can have different data types in the same column.

• A table can have repeating groups of values.

• A table must have atomic values, unique column names, and consistent data types in each column.

• A table must have at least one empty column.

Can a table in 1NF have repeating groups? Why or why not?

• Repeating groups are allowed if they are in separate columns.

• No, a table in 1NF cannot have repeating groups.

• A table in 1NF can have multiple primary keys.

• Yes, a table in 1NF can have repeating groups.

What is the main requirement for a table to be in Second Normal Form (2NF)?

• All attributes must be dependent on at least one non-key attribute.

• The table must have a composite primary key.

• All non-key attributes must be fully functionally dependent on the primary key.

• There can be no repeating groups in the table.

How does 2NF address partial dependency?

• 2NF requires that all attributes are independent of the primary key.

• 2NF maintains partial dependency by allowing some attributes to depend on a subset of the key.

• 2NF allows partial dependency by grouping non-key attributes.

• 2NF eliminates partial dependency by ensuring all non-key attributes depend on the entire primary key.

What is the definition of a functional dependency in the context of 2NF?

• A scenario where a primary key is dependent on a non-key attribute.

• A relationship where a non-key attribute is dependent on another non-key attribute.

• A condition where all attributes are dependent on a composite key.

• A relationship where a non-key attribute is fully dependent on the primary key, with no partial dependencies.

What are the criteria for a table to be in Third Normal Form (3NF)?

• A table is in 3NF if it is in 1NF and has no duplicate rows.

• A table is in 3NF if it has no primary key.

• A table is in 3NF if it contains only atomic values.

• A table is in 3NF if it is in 2NF and has no transitive dependencies.

How does 3NF eliminate transitive dependency?

• 3NF allows non-key attributes to depend on other non-key attributes.

• 3NF eliminates transitive dependency by removing all non-key attributes.

• 3NF eliminates transitive dependency by ensuring that non-key attributes are only dependent on the primary key, not on other non-key attributes.

• 3NF requires all attributes to be dependent on multiple keys.

What is an example of a transitive dependency?

• If A -> B and C -> D, then A -> D is a transitive dependency.

• If A -> B and A -> C, then A -> C is a transitive dependency.

• If A -> B and B -> A, then A -> C is a transitive dependency.

• If A -> B and B -> C, then A -> C is a transitive dependency.