Unit 3

Question 1

What is Normal Form & what it’s types

Answer 1

🔵Normal forms are like rules or guidelines to store data in a table effectively to avoid redundancy duplication of data,reduce updation cost & improve data integrity.

🔵Each normal forms builds based on the previous one.

🔵1NF, 2NF, 3NF,BCNF(Boyce - Codd Normal Form),4NF,5NF.

Question 2

Define Normalization & purpose of Normalization

Answer 2

Normalization is the process of organizing the data to reduce redundancy and improve integrity. It involves breaking database into two or more tables and defining relationship s between them.

The goal is to ensure that the database is easy to maintain and insertion, updation, deletion don’t lead to inconsistency.

Question 3

1NF

Answer 3

In the 1NF each column should have only one piece of information i.e atomic values or indivisible.

Question 4

Functional Dependency

Answer 4

FD means one piece of information can determine the another piece of information.

Example:

Student table

If we know roll number of a student, we can figure out the name of the student.

We can say

Roll number 👉name

This means roll number functionaly determines the student name.

Functional dependency reduces redundancy