The SQL Server GROUP BY clause is used in collaboration with the SELECT statement to arrange identical data into groups.
The GROUP BY clause follows the WHERE clause in a SELECT statement and precedes the ORDER BY clause.
Syntax
Following is the basic syntax of the GROUP BY clause. The GROUP BY clause must follow the conditions in the WHERE clause and must precede the ORDER BY clause if one is used.
SELECT column1, column2
FROM table_name
WHERE [ conditions ]
GROUP BY column1, column2
ORDER BY column1, column2
Example
Consider the CUSTOMERS table is having the following records −
ID NAME AGE ADDRESS SALARY
1 Ramesh 32 Ahmedabad 2000.00
2 Khilan 25 Delhi 1500.00
3 kaushik 23 Kota 2000.00
4 Chaitali 25 Mumbai 6500.00
5 Hardik 27 Bhopal 8500.00
6 Komal 22 MP 4500.00
7 Muffy 24 Indore 10000.00
If you want to know the total amount of salary on each customer, then the following will be the GROUP BY query.
SELECT NAME, SUM(SALARY) as [sum of salary] FROM CUSTOMERS
GROUP BY NAME;
The above command will produce the following output.
NAME sum of salary
Chaitali 6500.00
Hardik 8500.00
kaushik 2000.00
Khilan 1500.00
Komal 4500.00
Muffy 10000.00
Ramesh 2000.00
Let us now consider the following CUSTOMERS table having the following records with duplicate names.
ID NAME AGE ADDRESS SALARY
1 Ramesh 32 Ahmedabad 2000.00
2 Khilan 25 Delhi 1500.00
3 kaushik 23 Kota 2000.00
4 Chaitali 25 Mumbai 6500.00
5 Hardik 27 Bhopal 8500.00
6 Komal 22 MP 4500.00
7 Muffy 24 Indore 10000.00
If we want to know the total amount of salary on each customer, then the following will be GROUP BY query.
SELECT NAME, SUM(SALARY) as [sum of salary] FROM CUSTOMERS
GROUP BY NAME
The above command will produce the following output.
NAME sum of salary
Hardik 8500.00
kaushik 8500.00
Komal 4500.00
Muffy 10000.00
Ramesh 3500.00