Question

是否可以在加入过程中使用选择...

我正在尝试执行以下操作：

FROM 
tblorders o 
INNER JOIN tblunits u on o.id = u.orderid
INNER JOIN ((SELECT
                   ,Min(n.date) as [MinDate]
              from tblNotes n
             Where n.test = 'test') te
INNER JOIN tblnotes n on te.id = n.id
                     and te.[MinDate] = n.AuditinsertTimestamp)
INNER Join tblClient c ON o.ClientId = c.Id

基本上在查询中间的选择中，它只选择带有最小日期的音符。问题是我需要在这里做这个，因为我需要从tblOrders成为第一个表.......

建议？

Answer 1

INNER JOIN失败，因为你在这里有一个引导逗号：

,Min(n.date) as [MinDate]

我认为你正在寻找这样的东西：

SELECT ...
FROM tblorders o   
INNER JOIN tblunits u on o.id = u.orderid  
INNER JOIN (
    SELECT id, Min(date) as [MinDate]  
    from tblNotes 
    Where test = 'test'  
    group by id
) te  <-- not sure what JOIN clause to use here, please post schema
INNER JOIN tblnotes n on te.id = n.id  
    and te.[MinDate] = n.AuditinsertTimestamp  
INNER Join tblClient c ON o.ClientId = c.Id

Answer 2

您缺少别名和加入条件：

FROM 
tblorders o 
INNER JOIN tblunits u on o.id = u.orderid
INNER JOIN ((SELECT Min(n.date) as [MinDate]
              from tblNotes n
             Where n.test = 'test') te
INNER JOIN tblnotes n on te.id = n.id
                     and te.[MinDate] = n.AuditinsertTimestamp)
-- missing
AS z
ON <join conditions haere>
INNER Join tblClient c ON o.ClientId = c.Id

Answer 3

是的，您可以选择加入。

SQL在内连接的中间使用嵌套选择

3 个答案: