SQL - SUM Function

The SUM() function is an aggregate function that is used to find the sum (addition) of the given column or an expression. It can be applied on the numeric values or numeric columns only.

Syntax:

SELECT SUM(column_name)
FROM table_name
[WHERE condition];

For the demo purpose, we will use the following Employeetable in all examples.

The following query calculates the total salary of all the employees.

SELECT SUM(Salary) AS "Total Salary" FROM Employees;

You can also calculate the total salary of each department using the following query:

SELECT DeptId, SUM(Salary) AS "Department wise Total Salary" FROM Employee 
GROUP BY DeptId;