在LEFT JOIN查询中获取第一个表的属性

Question

考虑表格：

工人

和WorkersBosses（多对多）

我如何让所有员工与他们的老板（如果一个工人有一个老板，所以把它放在他身边，否则只是放一个空）。

有了这个：

SELECT TOP 1000 [EmployeeName] ,workboss.bossid
  FROM [TestingDB].[dbo].[Worker] as workers
  LEFT OUTER JOIN [TestingDB].[dbo].[WorkersBosses] as workboss
  on workers.EmployeeId = workboss.WorkerId

我让所有员工都带着他们的老板，但我怎么能得到老板的名字（而不仅仅是他的身份证）？

由于

Answer 1

将INNER JOIN添加到Worker：

SELECT
    w.EmployeeName AS EmployeeName,
    wb.BossName
FROM Worker w
LEFT JOIN(
    SELECT b.WorkerId, b.BossId, w2.EmployeeName AS BossName
    FROM WorkersBoss b
    INNER JOIN Worker w2
        ON w2.EmployeeId = b.BossId 
)wb
    ON w.EmployeeId = wb.WorkerId

这也可以写成：

SELECT
    w.EmployeeName AS EmployeeName,
    w2.EmployeeName AS BossName
FROM Worker w
LEFT JOIN WorkersBosses wb
    INNER JOIN Worker w2
        ON w2.EmployeeId = wb.BossId
    ON w.EmployeeId = wb.WorkerId

Answer 2

只需使用不同的别名即可多次加入同一个表：

SELECT w.EmployeeId,
    w.EmployeeName,
    b.EmployeeId AS BossEmployeeId,
    b.EmployeeName AS BossEmployeeName
FROM Worker w
LEFT JOIN WorkersBosses wb
    ON wb.WorkerId = w.EmployeeId
LEFT JOIN Worker b
    ON b.EmployeeId = wb.BossId