1
在下面的例子中,我需要知道如何将值MGR.manager_name
设置为''
(空字符串)时的值为MGR.report_to = 'A'
。基本上,当MGR.report_to ='A'
,员工将没有经理和manager_name将是空的。我无法获得下面的代码来工作。有没有另外一种方法来重新编写这个文件来让它起作用。谢谢! JKCASE在SELECT和JOIN中分配一个新值到列
SELECT
EMP.employee_id AS emplid,
EMP.employee_first_name AS firstname,
EMP.employee_last_name AS lastname,
EMP.employee_address AS address,
CASE MGR.manager_name
WHEN MGR.report_to ='A' THEN ''
THEN 'B'
ELSE 'C'
END AS managername,
MGR.manager_id AS managerid,
MGR.report_to
FROM Employee_Table EMP
LEFT OUTER JOIN Manager_Table MGR ON EMP.employee_id = MGR.employee_id