The HAVING Clause
The HAVING clause was added to SQL because the WHERE keyword could not be used with aggregate functions.SQL HAVING Syntax
SELECT column_name, aggregate_function(column_name) FROM table_name WHERE column_name operator value GROUP BY column_name HAVING aggregate_function(column_name) operator value
SQL HAVING Example
We have the following "Orders" table:| O_Id | OrderDate | OrderPrice | Customer |
|---|---|---|---|
| 1 | 2008/11/12 | 1000 | Hansen |
| 2 | 2008/10/23 | 1600 | Nilsen |
| 3 | 2008/09/02 | 700 | Hansen |
| 4 | 2008/09/03 | 300 | Hansen |
| 5 | 2008/08/30 | 2000 | Jensen |
| 6 | 2008/10/04 | 100 | Nilsen |
We use the following SQL statement:
SELECT Customer,SUM(OrderPrice) FROM Orders GROUP BY Customer HAVING SUM(OrderPrice)<2000
| Customer | SUM(OrderPrice) |
|---|---|
| Nilsen | 1700 |
We add an ordinary WHERE clause to the SQL statement:
SELECT Customer,SUM(OrderPrice) FROM Orders WHERE Customer='Hansen' OR Customer='Jensen' GROUP BY Customer HAVING SUM(OrderPrice)>1500
The result-set will look like this:
| Customer | SUM(OrderPrice) |
|---|---|
| Hansen | 2000 |
| Jensen | 2000 |





