The document discusses normalization in relational databases, highlighting its goals such as eliminating redundant data, enforcing consistency, and ensuring logical data dependencies. It outlines the problems associated with non-normalized data structures through a student registration system example and explains the advantages of normalization, including reduced space usage and improved data integrity. However, it also notes disadvantages like the complexity and time required for normalization, particularly in large databases.

1. PRESENTED BY SHWE YEE MYA WIN 03/02/2016
IMPORTANCE OF
NORMALIZATION

2. AGENDA
 What is normalization?
 Goals of performing normalization
 Advantages and disadvantages of normalization

3. WHAT IS NORMALIZATION?
 The process of reorganizing data structure in an efficient way in
designing relational database.
 Usually involves the processes of dividing a group of data into two or
more tables, defining the columns and keys within each table and
identifying the relationships between them.

4. MAIN GOALS OF PERFORMING
NORMALIZATION
 to eliminate redundant data (making sure that all data is stored in only one
place)
 to enforce data consistency
 to ensure data dependencies to be logical (meaning that data is stored in
the correct table)
 to isolate data (so that the changes made to a field or table does not affect
others)

5. EXAMPLE
What could happen if we do not perform normalization
process for Student Registration system and use a
single table that stores all the information of students,
courses and section details ?

6. WE WILL FACE THE FOLLOWING
PROBLEMS:
1. When we are inserting details of registered students, the details of their
registered courses and sections will also need to be entered for every
student record, thus course and section details will be repeated with
multiple records, result in storing duplicate data for courses and
sections.

7. 2. While updating a course or section details, we have to update the same
course or section for various students, which may lead to data
inconsistency if any record is left while updating.
3. If a course or section is closed, then deleting course or section record
will also delete the
student records, resulting in missing records.

8. But if we perform the process of normalization,
students, courses and section details records will split into 3 or more
tables that are linked by primary key and foreign keys eliminating
duplicate records, data redundancy and making data consistent
across all tables.

9. ADVANTAGES GAINED FROM USING
NORMALIZATION
 Elimination of data redundancy makes the database to be compact
reducing the overall amount of space a database consumes.
 Enforcement of referential integrity on data ensuring data to be
consistent across all table.
 Maintenance becomes easier and faster since the data are organized
logically in a normalized database in a flexible way.
 Searching and sorting of records is easier and faster because data will
appear in a separate, smaller table when a database is normalized
allowing us to easily find them.

10. DISADVANTAGES OF USING NORMALIZATION
 Can be very difficult and time consuming process to normalize the
relevant data for large and complex business with considerable amounts
of information.
 Require detailed analysis and design to perform normalization because
a poorly normalized database may perform badly and store data
inefficiently.
 A highly normalized database with many tables and joins between the
tables can slow down the database performance.
 Can also make database to be more complex because data is separated
into so many different tables.

11. REFERENCES
http://www.sqlservercentral.com/blogs/abhijit_desai/2010/09/07/no
ramlization/
http://www.webopedia.com/TERM/N/normalization.html
https://www.quora.com/Why-the-need-for-normalization
http://www.ehow.com/info_8072774_advantages-disadvantages-
normalizing-database.html