In relational database management system , normalisation is a concept in which database is managed in a way to reduce duplicay(redundancy).Normalisation involves dividing of larger tables into smaller tables mainly to reduce redundacy.
So five NF(normal forms) were developed for solution.
Edgar F Codd developed 1 NF ,and he was the first inventor of relational database .With need other NF developed.But before to study NF some terms may you know are as follow:-
Functional dependency: In relation R ,X is an attribute which is functionally dependent on Y.
That is X→Y .
In this Student Id → Student Sem ; means every value of column 1 is associated with precisely one value of column 2
So five NF(normal forms) were developed for solution.
Edgar F Codd developed 1 NF ,and he was the first inventor of relational database .With need other NF developed.But before to study NF some terms may you know are as follow:-
Functional dependency: In relation R ,X is an attribute which is functionally dependent on Y.
That is X→Y .
Example:
| Student Id | Student Sem | Lecture Time |
| 101 | 6 | 1:00A.M. |
| 101 | 4 | 3:00P.M. |
| 101 | 6 | 2:00P.M. |
In this Student Id → Student Sem ; means every value of column 1 is associated with precisely one value of column 2