1 What is functional dependencyOne attribute determinesanoth

1. What is functional dependency?One attribute determinesanother attribute

2. What is 1NF? No Multi-valued Attributes and PK identified

3. What is 2NF?1NF + No partial dependency

4. What is 3NF?2NF + No transitive dependency

5. What is partial dependency? Non-key determines part of PK

6. What is transitive dependency? Non-key determines another Non-key

7. What is full dependency? Non-key fully depends on PK

8. Why normalization is needed? Reduce data redundancy

Solution

Ans 1)

Functional dependency is said to be a relationship that comes into picture when one attribute uniquely identifies another attribute.Functional dependency is a constraint between two sets of attributes. Defining functional dependency is an important aspect of relational database design and it contributes to normalization.

Ans2)According to First Normal Form, no Rows of data must have repeating group of information. This means that each arrangement of column must consist of unique value in such a way that there is no multiple columns to fetch the same row.

Ans 3) The Second Normal Form says that there should not be partial dependency of any column with respect to the primary key.

Ans 4)Third Normal form states that every non-prime field of table must depend on primary key, or alternatively, there should be no non-prime attribute that gets determined by another non-prime attribute.