Question

任务：

表EmployeesInfo包含列：EmplId，EmplName，EmplCar，ChiefId 任务：选择只有首席分配的员工，分配的负责人必须有车，并且应该至少有三个直接下属（Chief的直接下属是在他的ChiefID专栏中具有主要权限的员工）。

输出列：EmplId，EmplName，ChiefId，ChiefCar，下属次数

注意： Chief也是ChiefId = NULL的员工。

问题： 这项任务的最佳解决方案是什么？我有一个，但我觉得它太可怕了。

添加：我正在使用SQL Server。如果您将使用它来解决此任务将是非常好的。谢谢。

我的解决方案：

SELECT E.EmpId, E.EmpName, E.ChiefId, B.EmpCar AS [Chief Car]
,
(SELECT COUNT(EE.EmpId) FROM EmployeeInfo AS EE
 INNER JOIN EmployeeInfo BB ON EE.ChiefId = BB.EmpId WHERE EE.ChiefId = E.ChiefId AND E.ChiefId IN
    (
        SELECT BB.EmpId
        FROM EmployeeInfo AS BB
        INNER JOIN EmployeeInfo AS EE
        ON BB.EmpId = EE.ChiefId
        GROUP BY BB.EmpId
        HAVING COUNT(EE.EmpId) >= 3
    )
) 
AS [Subordinate Count]

FROM EmployeeInfo AS B
LEFT JOIN EmployeeInfo AS E
ON E.ChiefId = B.EmpId
WHERE B.EmpCar IS NOT NULL AND E.ChiefId IN 
(
    SELECT B2.EmpId
    FROM EmployeeInfo AS B2
    INNER JOIN EmployeeInfo AS E2
    ON B2.EmpId = E2.ChiefId
    GROUP BY B2.EmpId
    HAVING COUNT(E2.EmpId) >= 3
);

部分数据：

其次是EmpId，EmpName，EmpCar，ChiefId

1，Emp1，NULL，4

2，Emp2，NULL，4

3，Emp3，NULL，4

4，Chief1，Somecar1，NULL

5，Emp4，NULL，7

6，Emp5，NULL，7

7，Chief2，Somecar2，NULL

期望的结果：

其次是EmpId，EmpName，ChiefId，ChiefCar，下属计数

1，Emp1,4，Somecar1,3

2，Emp2,4，Somecar1,3

3，Emp3,4，Somecar1,3

Answer 1

下面的解决方案可以帮助您，它在SQL中： -

SELECT distinct x.Employeeinfo from EmployeeInfo x, EmployeeInfo y
where y.CheflID IN (Select y.CheflID from EmployeeInfo y)
and x.CheflId=y.CheflID;

希望你能得到你正在寻找的东西......

Answer 2

可能的解决方案：

SELECT E.EmpId, E.EmpName, B.EmpId AS [Chief Id], B.EmpCar AS [Chief Car], 
(SELECT COUNT(EmpId) FROM Employees WHERE ChiefId = B.EmpId) AS [Subordinate Count]
FROM Employees AS E
INNER JOIN Employees AS B
ON E.ChiefId = B.EmpId
WHERE 3 <= (SELECT COUNT(EmpId) FROM Employees WHERE ChiefId = B.EmpId)
AND B.EmpCar IS NOT NULL

SQL任务的最佳解决方案

2 个答案: