Normalization is the part of the Dbms(Database Management System). To reduce the redundant, repeated or inconsistent and noise data we use normalization. Data base normalization is a database schema design technique, by which an already created schema is modified to minimize redundancy and dependency of the data. The main befits are we can eliminate data redundancy, it improves the performance of the DBMS, faster update etc.
Without normalization we may have
1. Data may be complex
2. Data may inadequate
3. Data may be the confusion
4. Changing the data i.e. updating, inserting, deleting may be the complex.
What normalization explains?
The normalization is the process to eliminate the problematic data created by the users. But the problems will not completely remove in the single step. So we have to follow some steps. The steps are called normalization forms/ normal forms.
In the first step or in the first attempt we will eliminate the following problems
As per first normal form, no two rows of data must contain repeating.
So eliminate to the flowing way
In the second normal form, it is based on the functional dependency. In this we are finding out the primary and non-primary attributes. Partial dependencies are not allowed in the second normal forms/.In the third normal form, the transitive functional dependencies should be removed from the table and the table must be in the second normal form. The next normal form is called BCNF (Boyce-codd normal form). If you have A and B functions. A AND B should be candidates keys. In the fourth normal form, it has no multiple sets of multi valve dependencies. If we decompose the tables to multiple numbers, then also there is no loss less is called the fifth normal form.
There may be some more normal forms to get good data, but I explained only 5 normal forms. Finally, the conclusion is from this article is that DBMS TABLES in to smaller with less redundant and without loss of information.
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Article By:
T. Pavan KumarAssist. Professor
CSE Department
Sphoorthy Engineering College
Without normalization we may have
1. Data may be complex
2. Data may inadequate
3. Data may be the confusion
4. Changing the data i.e. updating, inserting, deleting may be the complex.
What normalization explains?
The normalization is the process to eliminate the problematic data created by the users. But the problems will not completely remove in the single step. So we have to follow some steps. The steps are called normalization forms/ normal forms.
In the first step or in the first attempt we will eliminate the following problems
| Studentname | age | subject |
| Pavan | 30 | english,social |
| Rahul | 40 | maths |
| Kumar | 25 | Biology |
As per first normal form, no two rows of data must contain repeating.
So eliminate to the flowing way
| Studentname | age | subject |
| Pavan | 30 | english |
| Pavan | 30 | social |
| Rahul | 40 | maths |
| Kumar | 25 | Biology |
In the second normal form, it is based on the functional dependency. In this we are finding out the primary and non-primary attributes. Partial dependencies are not allowed in the second normal forms/.In the third normal form, the transitive functional dependencies should be removed from the table and the table must be in the second normal form. The next normal form is called BCNF (Boyce-codd normal form). If you have A and B functions. A AND B should be candidates keys. In the fourth normal form, it has no multiple sets of multi valve dependencies. If we decompose the tables to multiple numbers, then also there is no loss less is called the fifth normal form.
There may be some more normal forms to get good data, but I explained only 5 normal forms. Finally, the conclusion is from this article is that DBMS TABLES in to smaller with less redundant and without loss of information.
-------------------------------------------------------------
Article By:
T. Pavan KumarAssist. Professor
CSE Department
Sphoorthy Engineering College
 |
| Sphoorthy Engineering College |
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