SQL HAVING Clause
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 conditionORDER 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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