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The SQL HAVING Clause

The HAVING clause is used to filter the results of a GROUP BY query based on aggregate functions.

Unlike the WHERE clause, which filters individual rows before grouping, the HAVING clause filters groups after the aggregation has been performed.

HAVING Syntax

SELECT
column1, aggregate_function(column2), column3, ...
FROM
table_name
WHERE
condition
GROUP BY
column1
,
column3
HAVING
condition
 -- The condition on grouped data
ORDER BY
column_name
;

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 ConstituciÃ³n 2222	MÃ©xico D.F.	05021	Mexico
3	Antonio Moreno TaquerÃa	Antonio Moreno	Mataderos 2312	MÃ©xico D.F.	05023	Mexico
4	Around the Horn	Thomas Hardy	120 Hanover Sq.	London	WA1 1DP	UK
5	Berglunds snabbkÃ¶p	Christina Berglund	BerguvsvÃ¤gen 8	LuleÃ¥	S-958 22	Sweden

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....