Adventure Query for SQL Query

Question

我的任务是找到在2个部门工作过的员工的姓名，我觉得我的格式是不正确的，因为它只显示1个结果，它意味着回来4，如果有人可以查看它如果我有一些非常感激的语法错误，请告诉我。

SELECT P.FirstName,LastName, COUNT(D.DepartmentID) as Departments
FROM HumanResources.EmployeeDepartmentHistory D
INNER JOIN Person.Person P ON P.BusinessEntityID = D.DepartmentID 
GROUP BY P.FirstName,LastName
HAVING COUNT(DepartmentID)=2

Answer 1

ON P.BusinessEntityID = D.DepartmentID - 不会给出明智的结果 试试ON P.BusinessEntityID = D.BusinessEntityID