Question

我需要找到其主管的主管SSN为'888665555'的所有员工

我似乎无法弄清楚我做错了什么。

以下是正在使用的表的副本。

Fname    Lname   Ssn       Super_ssn
john     smith   123456789 333445555
franklin wong    333445555 888665555
alicia   zelaya  999887777 987654321
jennifer wallace 987654321 888665555
ramesh   narayan 666884444 333446666
joyce    english 453453453 333445555
ahmad    jabbar  987987987 987654321
james    borg    888665555 NULL

我一直在尝试的SQL代码如下。

SELECT EMPLOYEE.Fname, EMPLOYEE.Lname
FROM EMPLOYEE
WHERE EMPLOYEE.Super_ssn =
(SELECT EMPLOYEE.Ssn 
FROM EMPLOYEE
WHERE EMPLOYEE.Super_ssn = '888665555');

结果应如下所示：

Fname  Lname
john   smith
alicia zelaya
ramesh narayan
joyce  english
ahmad  jabbar

Answer 1

感谢NSNoob，我找到了答案。

SELECT EMPLOYEE.Fname, EMPLOYEE.Lname
FROM EMPLOYEE
WHERE EMPLOYEE.Super_ssn IN
(SELECT EMPLOYEE.Ssn 
FROM EMPLOYEE
WHERE EMPLOYEE.Super_ssn = '888665555');

这会获取每个结果，而不是仅接受一个结果。

Answer 2

下面的子查询返回的结果不止一个。

(SELECT EMPLOYEE.Ssn 
FROM EMPLOYEE
WHERE EMPLOYEE.Super_ssn = '888665555');

像

一样修改它

 (SELECT top 1 EMPLOYEE.Ssn 
    FROM EMPLOYEE
    WHERE EMPLOYEE.Super_ssn = '888665555');

或类似的东西，它只通过子查询返回一个结果。

Answer 3

MS Access sql没有递归选择。但是，如果您知道深度，则可以执行标准（双）连接。问题是你的主管只有一名超级监督员吗？

如果您只有两个级别：尝试此查询：

    SELECT 
    tbl_employee.fname,
    tbl_employee.lname,
    tbl_employee_supervisor.ssn,
    tbl_employee_super_supervisor.ssn
FROM
    (tbl_employee
    LEFT JOIN tbl_employee AS tbl_employee_supervisor ON tbl_employee.super_ssn = tbl_employee_supervisor.ssn)
        LEFT JOIN
    tbl_employee AS tbl_employee_super_supervisor ON tbl_employee_supervisor.super_ssn = tbl_employee_super_supervisor.ssn
WHERE
    (((tbl_employee_supervisor.ssn) = '888665555'))
        OR (((tbl_employee_super_supervisor.ssn) = '888665555'));

结果：

fname   lname   supervisor.ssn  super_supervisor.ssn
john    smith   333445555   888665555
franklin    wong    888665555   
alicia  zelaya  987654321   888665555
jennifer    wallace 888665555   
joyce   english 333445555   888665555
ahmad   jabbar  987654321   888665555

查找主管主管是特定人员的员工

3 个答案: