The SQL HAVING Clause
The HAVING clause was added to SQL because the WHERE keyword could not be used with aggregate functions.
HAVING Syntax
SELECT column_name(s)
FROM table_name
WHERE condition
GROUP BY column_name(s)
HAVING condition
ORDER BY column_name(s);
Demo Database
Below is a selection from the "Customers" table in the Northwind sample database:
CustomerID | CustomerName | ContactName | Address | City | PostalCode | Country |
---|---|---|---|---|---|---|
1 | Alfreds Futterkiste | Maria Anders | Obere Str. 57 | Berlin | 12209 | Germany |
2 | Ana Trujillo Emparedados y helados | Ana Trujillo | Avda. de la Constitución 2222 | México D.F. | 05021 | Mexico |
3 | Antonio Moreno Taquería | Antonio Moreno | Mataderos 2312 | México D.F. | 05023 | Mexico |
4 | Around the Horn | Thomas Hardy | 120 Hanover Sq. | London | WA1 1DP | UK |
5 | Berglunds snabbköp | Christina Berglund | Berguvsvägen 8 | Luleå | S-958 22 | Sweden |
SQL HAVING Examples
The following SQL statement lists the number of customers in each country. Only include countries with more than 5 customers:
Example
SELECT COUNT(CustomerID), Country
FROM Customers
GROUP BY Country
HAVING COUNT(CustomerID) > 5;
The following SQL statement lists the number of customers in each country, sorted high to low (Only include countries with more than 5 customers):
Example
SELECT COUNT(CustomerID), Country
FROM Customers
GROUP BY Country
HAVING COUNT(CustomerID) > 5
ORDER BY COUNT(CustomerID) DESC;
Demo Database
Below is a selection from the "Orders" table in the Northwind sample database:
OrderID | CustomerID | EmployeeID | OrderDate | ShipperID |
---|---|---|---|---|
10248 | 90 | 5 | 1996-07-04 | 3 |
10249 | 81 | 6 | 1996-07-05 | 1 |
10250 | 34 | 4 | 1996-07-08 | 2 |
And a selection from the "Employees" table:
EmployeeID | LastName | FirstName | BirthDate | Photo | Notes |
---|---|---|---|---|---|
1 | Davolio | Nancy | 1968-12-08 | EmpID1.pic | Education includes a BA.... |
2 | Fuller | Andrew | 1952-02-19 | EmpID2.pic | Andrew received his BTS.... |
3 | Leverling | Janet | 1963-08-30 | EmpID3.pic | Janet has a BS degree.... |
More HAVING Examples
The following SQL statement lists the employees that have registered more than 10 orders:
Example
SELECT Employees.LastName, COUNT(Orders.OrderID) AS NumberOfOrders
FROM (Orders
INNER JOIN Employees ON Orders.EmployeeID = Employees.EmployeeID)
GROUP BY LastName
HAVING COUNT(Orders.OrderID) > 10;
Try it Yourself »The following SQL statement lists if the employees "Davolio" or "Fuller" have registered more than 25 orders:
Example
SELECT Employees.LastName, COUNT(Orders.OrderID) AS NumberOfOrders
FROM Orders
INNER JOIN Employees ON Orders.EmployeeID = Employees.EmployeeID
WHERE LastName = 'Davolio' OR LastName = 'Fuller'
GROUP BY LastName
HAVING COUNT(Orders.OrderID) > 25;
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