Functional Dependency

 The functional dependency is a relationship that exists between two 

attributes. It typically exists between the primary key and non-key 

attribute within a table.

1. X → Y 

The left side of FD is known as a determinant, the right side of the 

production is known as a dependent.

For example:

Assume we have an employee table with attributes: Emp_Id, 

Emp_Name, Emp_Address.

Here Emp_Id attribute can uniquely identify the Emp_Name

attribute of employee table because if we know the Emp_Id, we can 

tell that employee name associated with it.


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