Username Employee_Name Is_Employed L4_Username aaa123 A1 Y aaa131 aaa124 A2 Y aaa131 aaa125 A3 Y aaa131 aaa126 A4 Y aaa131 aaa127 A5 Y aaa131 aaa128 A6 Y aaa131 aaa129 A7 Y aaa131 aaa130 A8 Y aaa130 aaa131 A9 Y aaa130
我需要对此数据执行的操作是尝试并创建一个可以找到aaa131（例如）的语句并返回该L4_Username的员工名称并将其显示为AS L4_Employeename，以便我得到以下内容：
Username Employee_Name Is_Employed L4_Username L4_Employeename aaa123 A1 Y aaa131 A9 aaa124 A2 Y aaa131 A9 aaa125 A3 Y aaa131 A9 aaa126 A4 Y aaa131 A9 aaa127 A5 Y aaa131 A9 aaa128 A6 Y aaa131 A9 aaa129 A7 Y aaa131 A9 aaa130 A8 Y aaa130 A8 aaa131 A9 Y aaa130 A8
它基本上需要像索引匹配一样并返回employee_name AS L4_EmployeeName
有什么想法吗？
这是我开始的地方
SELECT *
FROM Employee_Team a
INNER JOIN Workforce_Detail b ON a.Username = b.Username
WHERE Is_Employed = 'Y'
编辑：根据评论，我不清楚哪些表格有什么：