如何在MySQL中使用count函數的結果？

Question

我需要做一個查詢計數有多少員工在有超過1名員工並與員工數量大於或等於6每個部門，我有：

Select DepartmentName, count(EmployeeNumber) as "Number of Employees" 
From department d, employee e 
Where d.DepartmentName = e.Department and e.EmployeeNumber <=6 
Group by d.DepartmentName; 

這充滿除了關於有部分的所有要求超過1名員工，有沒有辦法只執行代碼的其餘部分，從第一行返回2或更大的結果？

Answer 1

使用HAVING子句。請注意，在整個事情計算完畢後纔會應用它。

Select DepartmentName, count(EmployeeNumber) as "Number of Employees" 
From department d, employee e 
Where d.DepartmentName = e.Department and e.EmployeeNumber <=6 
Group by d.DepartmentName HAVING count(EmployeeNumber) > 1; 

Answer 2

試試這個

Select DepartmentName, count(EmployeeNumber) as "Number of Employees" 
    From department d, employee e 
    Where d.DepartmentName = e.Department 
    Group by d.DepartmentName and e.EmployeeNumber <=6 
    HAVING count(EmployeeNumber) > 1 ;