Question

2NF to 3NF means to remove ____

a) Duplicate rows
b) Duplicate columns
c) Partial dependencies
d) Transitive dependencies

Answer 1

To convert a relation from 2NF to 3NF, we remove partial dependencies by splitting attributes that are functionally dependent on only part of the primary key.

Step-by-step explanation:

To convert a relation from 2NF to 3NF, the goal is to remove partial dependencies. Partial dependencies occur when a non-key attribute is functionally dependent on only a part of the primary key. By eliminating partial dependencies, we can achieve a higher level of normalization and reduce redundancy in the database.

For example, let's say we have a relation called 'Students' with attributes such as 'Student ID', 'First Name', 'Last Name', and 'Address'. If the 'Address' attribute is functionally dependent on only the 'Student ID' attribute, it is a partial dependency. To convert to 3NF, we would separate the 'Address' attribute into a separate relation that is only dependent on the 'Student ID'.

In summary, to convert from 2NF to 3NF, we remove partial dependencies by splitting attributes that are functionally dependent on only part of the primary key.