Listing 5. Using GROUP BY ALL to Include Employees with No Orders in the Result Set

SELECT E.EmployeeID, E.FirstName,
   E.LastName, E.Country,
   COUNT(*) AS NumOrders
FROM dbo.Employees AS E
  JOIN dbo.Orders AS O
    ON O.EmployeeID = E.EmployeeID
WHERE E.Country = 'USA'
GROUP BY ALL E.EmployeeID,
   E.FirstName, E.LastName,
     E.Country;