Normalization & types of normalization along with examples

1. NORMALIZATION

2. NORMALIZATION
❖ Technique to remove or reduce redundancy from table.
S_ID S_NAME AGE
1 RAM 20
2 VARUN 25
1 RAM 20
←
←
“NORMALIZATION divides the tables into subtables to reduce redundancy”

3. 1NF ➔ Table should not contain any multivalued attributes.
ROLL_NO NAME COURSE
1 SAI C/C++
2 HARSH JAVA
3 ONKAR C/DBMS
ROLL_NO NAME
1 SAI
2 HARSH
3 ONKAR
ROLL_NO COURSE
1 C
1 C++
2 JAVA
3 C
3 DBMS
Not in 1st NF
1st NF
Primary Key = ROLL_NO
Primary Key = ROLL_NOCOURSE

4. 2NF
➔ Table must be in 1NF
➔ All Non-prime attributes should be fully functional dependent
on candidate key
C_ID STORE_ID LOCATION
1 1 DELHI
1 3 MUMBAI
2 1 DELHI
3 2 BANGLORE
4 3 MUMBAI
Candidate key = C_IDSTORE_ID
Prime attributes = C_ID, STORE_ID
Non-Prime attributes = LOCATION
2nd NF C_ID STORE_ID
1 1
1 3
2 1
3 2
4 3
STORE_ID LOCATION
1 DELHI
2 BANGLORE
3 MUMBAI
P.K = C_IDSTORE_ID
C.K = STORE_ID
Non-Prime = LOCATION

5. 3NF
➔ Table must be in 2NF.
➔ There should be no transition dependency in table.
Prime attributes = ROLL_NO
Non-Prime attributes = NAME, COURSE, FEES
Functional Dependency = ROLL_NO -> NAME ✔
COURSE ->FEES ✖
3rd NF
ROLL_NO NAME COURSE FEES
1 AKASH C 100
2 PRATIK C++ 200
3 MAHESH C 100
4 OM JAVA 300
ROLL_NO NAME COURSE
1 AKASH C
2 PRATIK C++
3 MAHESH C
4 OM JAVA
COURSE FEES
C 100
C++ 200
JAVA 300
Functional Dependency = ROLL_NO -> NAME ✔
ROLL_NO -> COURSE ✔
Prime
Non-Prime Non-Prime
Prime
Non-Prime
Functional Dependency = COURSE -> FEES ✔