Generalized Projection Operation, Aggregation Operation in Python

Let’s consider the following table and understand these operations with examples.

R1 :    FACULTY-1

Generalized Projection Operation ( P ) : 

This operation allows arithmetic operations or string operations in the attribute list of projection operations.

Example-1 :  Find the list of FName having PhD degree and their 10 %  of Salaries.

    P FName, Salary ¸ 10  (sQual = ‘PhD’ (Faculty-1)

Output :                

Aggregation Operation : (   ) 

Aggregate Function takes a collection of values and returns a single value as a result.

Example-2 :  Find the sum of the salaries of all the faculty.

              (Faculty-1)

              sum(Salary)

Output :                       396000

Example-3 :  Find the average of the salaries of all the faculty

                                              (Faculty-1)

                                              average(Salary)

Output :                            39600