以下SQL语句列出已注册超过10个订单的员工: 
 
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; 
 以下SQL语句列出员工“Davolio”或“Fuller”是否已注册超过25个订单: 
 
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; |