SQL Select Sum

SELECT SUM() is used to return the sum of all values in one specified column. SUM function is applies on numeric or numeric related fields.

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

column_name – Represents the name of the column on which sum operation performed.
table_name - Represents the name of the table.

Let us consider below table(s) as an example table(s) to frame the SQL query for getting the desired results.

emp_id	emp_name	designation	manager_id	date_of_hire	salary	dept_id
001	Employee1	Director		2019-07-11	45000.00	1000
002	Employee2	Director		2019-07-11	40000.00	2000
003	Employee3	Manager	Employee1	2019-07-11	27000.00	1000
004	Employee4	Manager	Employee2	2019-10-08	25000.00	2000
005	Employee5	Analyst	Employee3	2019-07-11	20000.00	1000
006	Employee6	Analyst	Employee3	2019-10-08	18000.00	1000
007	Employee7	Clerk	Employee3	2019-07-11	15000.00	1000
008	Employee8	Salesman	Employee4	2019-09-09	14000.00	2000
009	Employee9	Salesman	Employee4	2019-10-08	13000.00	2000

Scenario – Sum data without any condition.

Requirement– Get the sum of all employee salaries. The query was as follows –

SELECT SUM (salary) AS "Total Salary" FROM employee_details;

By executing above query, we can get results as shown below -

Total employees
9

Scenario – Sum data with WHERE condition.

Requirement - Get total salary for department 1000. The query was as follows –

SELECT SUM (salary) AS 'Total salary' 
FROM employee_details
WHERE dept_id = 1000;

By executing above query, we can get results as shown below –

Total salary
125000.00

Scenario – Sum data using GROUP BY clause.

Requirement – Get department wise total salaries. The query was as follows –

SELECT dept_id, SUM(Salary) AS "Total salary" 
FROM employee_details GROUP BY dept_id;

By executing above query, we can get results as shown below –

dept_id	Total salary
1000	125000.00
2000	92000.00