SQL SELECT SUM

It is also known as SQL SUM() function. It is used in a SQL query to return summed value of an expression.

Let's see the Syntax for the select sum function:

SELECT SUM (expression)
FROM tables
WHERE conditions;

expression may be numeric field or formula.

This would produce the following result.

After using this SQL SELECT SUM example, it will produce the result containing the sum of the salary greater than 20000.

Total salary: 116,000

If you want to know how the combined total salary of all employee whose salary is above 20000 per month.

SELECT SUM (salary) AS "Total Salary"
FROM employees
WHERE salary > 20000;

In this example, you will find the expression as "Total Salary" when the result set is returned.

You can also use SQL DISTINCT clause with SQL SUM function.

SELECT SUM (DISTINCT salary) AS "Total Salary"
FROM employees
WHERE salary > 20000;

Sometimes there is a need to use the SQL GROUP BY statement with the SQL SUM function.

For example, we could also use the SQL SUM function to return the name of department and the total sales related to department.

SELECT department, SUM (sales) AS "Total Sales"
FROM order_details
GROUP BY department;

Let us take a table named order_details

ID	DEPARTMENT	DATE	DAILY SALES
1	Mechanical	2012-08-13	360
2	Electrical	2012-08-13	100
2	Electrical	2012-08-14	110
3	Electronics	2012-08-13	150
3	Electronics	2012-08-14	170

After using the SQL GROUP BY statement with SUM, you will find the following result.

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