User of HAVING clause
SQL HAVING Clause
The SQL HAVING Clause
The HAVING
clause was added to SQL because the WHERE
keyword cannot 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;
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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