Normalization all normal forms explanation with table representation

1. Normalization

2. CONTENT
What is Normalization?
2
Data Redundancy
Anomalies
First Normal Form
Second Normal Form
Third Normal Form
Boyce -Codd Normal Form

3. 1.
What is
Normalization

4. “
Normalization is a technique of
organizing data into multiple related
tables ,to minimize Data Redundancy
4

5. Data Redundancy means repetition of data
5
Reason
Two different but related table stored together.
Issues
1. Repetition of data increases size of database
2. Causes Anomalies

6. Anomalies are problems that can occur in poorly planned , un-
normalized databases where all data is stored in same table
Types
To insert redundant data for every new row is a data insertion
anomaly.
Loss of related dataset when some other dataset is deleted is
a deletion anomaly.
A data inconsistency that results from data redudancy and
partial update is updation anomaly.

7. Roll No. Name Branch HOD Office_tel
1
A CS Mr.x 2342
2
B CS Mr.x 2342
3
B CS Mr.x 2342
4
D CS Mr.x 2342
Roll No. Name Branch HOD Office_tel
1
A CS Mr.x 2342
2
B CS Mr.x 2342
3
B CS Mr.x 2342
Roll No. Name Branch HOD Office_tel
1
A CS Mr.x 2342
2
B CS Mr.x 2342
Roll No. Name Branch HOD Office_tel
1
A CS Mr.x 2342
Roll No. Name Branch HOD Office_tel
Student Table
Insertion and Deletion Anomaly

8. Roll No. Name Branch HOD Office_tel
1
A CS Mr.x 2342
2
B CS Mr.x 2342
3
B CS Mr.x 2342
4
D CS Mr.x 2342
Roll No. Name Branch HOD Office_tel
1
A CS Mr.x Mr.y 2342
2
B CS Mr.x 2342
3
B CS Mr.x 2342
4
D CS Mr.x 2342
Roll No. Name Branch HOD Office_tel
1
A CS Mr.x Mr.y 2342
2
B CS Mr.x Mr.y 2342
3
B CS Mr.x 2342
4
D CS Mr.x 2342
Roll No. Name Branch HOD Office_tel
1
A CS Mr.x Mr.y 2342
2
B CS Mr.x Mr.y 2342
3
B CS Mr.x 2342
4
D CS Mr.x Mr.y 2342
Student Table
Updation Anomaly
Roll No. Name Branch HOD Office_tel
1
A CS Mr.x 2342
2
B CS Mr.x 2342
3
B CS Mr.x 2342
4
D CS Mr.x 2342

9. Roll No. Name BranchID
1 A 1
2 B 1
3 B 1
4 D 1
BranchID HOD Office_tel
1 Mr.x 2342
Student Table
Dept Table
By dividing Student Table into Student and
Department Table we can eliminate all anomalies .

10. 2.
1st Normal
Form

11. “
Every table in database should at least
follow the 1st normal form always . To be
in 1st normal form a table should follow
some rules.
11

12. ▪Each table should
contain atomic values
12
Rule 1
colour A
Yellow 10,20,22
Blue 30,22,22
Orange 52,22,12

13. ▪A column should
contain values of same
type
13
Rule 2
colour A
Yellow 22
Blue 22
12
Orange

14. ▪Each column should
have a unique name
Place your screenshot here
14
Rule 3 colour A A
Yellow 22 20
Blue 22 15
Orange
12
24
colour A B
Yellow 22 20
Blue 22 15
Orange
12 24

15. 3.
2st Normal
Form

16. “
For a table to be in second normal form :
▪It must be in 1st normal form
▪Their should be no partial dependency.
16

17. 17
StudentID Name RegNo Branch Address
1
Akon CSE-18 CSE UP
2
Akon IT-18 IT UK
3
Bkon CSE-18 CSE MP
4
Dkon CSE-18 CSE RAJ
STUDENT TABLE
SubjectID SubjectName
1 C
2 C++
SUBJECT TABLE
SubjectID
StudentID

18. 18
ScoreID StudentID SubjectID Marks Teacher
1 1 1 86 Mr.C
2 1 2 45 Mr.C++
3 3 1 98 Mr.C
4 2 1 78 Mr.C
SCORE TABLE
Partial Dependency
StudentID SubjectID Teacher
1. StudentID,SubjectID  ScoreID,Marks,Teacher
2. SubjectID  Teacher

19. 19
Now the tables are in second Normal Form....
SubjectID SubjectName Teacher
1
C Mr.C
2
C++ Mr.C++
SUBJECT TABLE
ScoreID StudentID SubjectID Marks
1 1 1 86
2 1 2 45
3 3 1 98
4 2 1 78
SCORE TABLE
StudentID SubjectID
SubjectID

20. 4.
3st Normal
Form

21. “
For a table to be in third normal form :
▪It must be in 2st normal form
▪Their should be no Transitive dependency.
21

22. 22
ScoreID StudentID SubjectID Marks Exam_Name Total_Marks
1 123 1 23 PracticalC 30
2 124 1 12
PracticalC
30
StudentID SubjectID Total_Marks
Transitive Dependency
Exam_Name
1. StudentID,SubjectID  ScoreID,ExamName,Total_marks
2. ExamName Total_Marks

23. 23
ScoreI
D
StudentI
D
SubjectID Mark
s
Teacher ExamID
1 123 1 23 Mr.C 1
2 124 1 12 Mr.C 1
Now the tables are in Third Normal Form....
ExamID Exam_N
ame
Total_Ma
rks
1
Practical
C
30
2
Practical
C++ 30
Student Table Exam Table

24. 5.
Boyce Codd
Normal Form

25. “
For a table to be in boyce-codd normal form :
▪It must be in 3rd normal form.
▪For any dependency A B ,A should be a
super key.
25

26. 26
StudentID Subject Professor
101 C++ p.Cpp
102 Python p.Python
103 Python p.Python2
104 Java p.java
COLLEGE ENROLLMENT TABLE
StudentID Subject

27. 27
StudentID Subject Professor
COLLEGE ENROLLMENT TABLE
StudentID Subject
(student_id,subject) Professor
Professor Subject
Non prime attribute Non prime attribute

28. 28
StudentID Professor
StudentID
Student Table
P ID Professor Subject
Student Table
P_ID
Professor Table
Now,our table is in BCNF

29. Thanks!
Any Questions ?
Presented By
•Manohar Bhasin
•Rishi Singh
•Sandeep kumar Singh