What is Normalization in Database Management System (DBMS) ? What is the history of the system of normalization? Types of Normalizations, and why this is needed all details in the presentation.

1. NORMALIZATION
Presented By:
 Rajat Ghosh
 Raunak Mallick
 Rishav Tiwary
 Tamal Sengupta

2. CONTETNTS
 Database Normalization
 History
 Types of Normalizations
 Objective of Normalization
 References

3. DATABASE NORMALIZATION
 Database normalization is the process of removing data
from your tables in to improve storage efficiency, data
integrity, and scalability.
 Normalization generally involves splitting existing tables
into multiple ones, which must be re-joined or linked
each time a query is issued.

4. HISTORY
 Edgar F. Codd first proposed the process of normalization
and what came to be known as the 1st normal form in his
paper A Relational Model of Data for Large Shared Data
Banks Code stated:
“There is, in fact, a very simple elimination procedure
which we shall call normalization. Through decomposition
non-simple domains are replaced by ‘domains whose
elements are atomic (non-decomposable) values’.”

5. TYPES OF NORMALIZATIONS
 Edgar F. Codd originally established three normal forms:
1NF, 2NF and 3NF. There are now others that are
generally accepted, but 3NF is widely considered to be
sufficient for most applications.

6.  Un-Normalized Relation:
Let's consider the STUDENT table with his ID, Name address and 2
subjects that he has opted for.
STUDENT
STUDENT_ID
STUDENT_NAME
ADDRESS
SUBJECT1
SUBJECT 2
STUDENT_ID STUDENT_NAME ADDRESS SUBJECT1 SUBJECT2
100 Rajat Guma History Geography
101 Raunak Barasat Mathematics Chemistry
102 Rishav Barasat Physics Biology
103 Tamal Habra English Computer

7. FIRST NORMAL FORM (1NF)
A table is said to be in First Normal Form (1NF) if and only
if each attribute of the relation is atomic. That is,
 Each row in a table should be identified by primary key (a
unique column value or group of unique column values)
 No rows of data should have repeating group of column
values.

8.  Example of 1NF:
STUDENT
STUDENT_ID
STUDENT_NAME
ADDRESS
SUBJECT
STUDENT_ID STUDENT_NAME ADDRESS SUBJECT
100 Rajat Guma History
100 Rajat Guma Geography
101 Raunak Barasat Mathematics
101 Raunak Barasat Chemistry
102 Rishav Barasat Physics
103 Tamal Habra Computer
1NF

9. SECOND NORMAL FORM (2NF)
A table is said to be in 2NF if both the following conditions hold:
 Table is in 1NF (First normal form)
 No non-prime attribute is dependent on the proper subset of any
candidate key of table.
 An attribute that is not part of any candidate key is known as non-
prime attribute.

10.  Example of 2NF: STUDENT_ID ADDRESS
100 Guma
101 Barasat
102 Barasat
103 Habra
STUDENT_ID STUDENT_NAME SUBJECT
100 Rajat History
100 Rajat Geography
101 Raunak Mathematics
101 Raunak Chemistry
102 Rishav Physics
102 Rishav Biology
103 Tamal English
103 Tamal Computer
STUDENT_ADDRESS Table
STUDENTS_DETAILSTable
2NF

11. THIRD NORMAL FORM (3NF)
A table is said to be in the Third Normal Form when:
 It is in the Second Normal form.
 And, it doesn't have Transitive Dependency.

12.  Example of 3NF:
STUDENT_ID STUDENT_NAME
100 Rajat
101 Raunak
102 Rishav
103 Tamal
STUDENT_ID SUBJECT
100 History
100 Geography
101 Mathematics
101 Chemistry
102 Physics
102 Biology
103 English
103 Computer
Student Table
SubjectTable
3NF

13. BOYCE CODD NORMAL FORM (BCNF)
 It is an advance version of 3NF that’s why it is also referred
as 3.5NF.
 BCNF is stricter than 3NF. A table complies with BCNF if it is
in 3NF and for every functional dependency X->Y, X should be
the super key of the table.

14.  Example of BCNF: STUDENT_ID ADDRESS
100 Guma
101 Barasat
102 Barasat
103 HabraSTUDENT_ID STUDENT_NAME
100 Rajat
101 Raunak
102 Rishav
103 Tamal
STUDENT_ID SUBJECT
100 History
100 Geography
101 Mathematics
101 Chemistry
102 Physics
102 Biology
103 English
103 Computer
ADDRESS Table
STUDENT Table
SUBJECTTable
BCNF

15. OBJECTIVE OF NORMALIZATION
 To free the collection of relations from undesirable
insertion, update and deletion dependencies.
 To make the relational model more informative to users.
 To make the collection of relations neutral to the query
statistics.

16. REFERENCES
 Classle [https://www.classle.net/submission/objectives-
normalization]
 Wikipedia [https://www.wikipedia.org/]

17. Thank You