「多部分組成的標識符不能被束縛」的錯誤

Question

我使用的是SQL Server 2005中我得到這個錯誤：

*The multi-part identifier "ms.MOP_desc" could not be bound.*

我測試了上述2個選擇查詢和他們工作得很好分別，但我當我結合這些查詢時出現錯誤。我可以告訴我這個查詢出了什麼問題嗎？謝謝。

SELECT SUM(Amount) AS TotalAmount, ms.MOP_desc 
FROM 
(
    SELECT SUM(hd.delivery_value) AS Amount, ms.MOP_desc 
    FROM TRANSACTION_HEADER AS th 
     INNER JOIN TRANSACTION_DETAIL AS td 
      ON th.transaction_number = td.transaction_number 
     LEFT JOIN hose_delivery hd 
      ON td.delivery_id = hd.delivery_id 
     LEFT JOIN product pr 
      ON pr.product_id = td.product_id 
     INNER JOIN MOP_Setting AS ms 
      ON hd.MOP_ID = ms.MOP_ID 
    WHERE hd.delivery_value > 0 
     AND (th.USER_PERIOD_ID IN (13)) 
     AND (hd.MOP_ID IN (1)) 
     AND hd.Cleared_By != '0' 
    GROUP BY ms.MOP_desc 

    UNION ALL 

    SELECT SUM(td.quantity * td.price_sold) AS Amount, ms.MOP_desc 
    FROM TRANSACTION_HEADER AS th 
     INNER JOIN TRANSACTION_DETAIL AS td 
      ON th.transaction_number = td.transaction_number 
     INNER JOIN MOP_Setting AS ms 
      ON th.MOP_ID = ms.MOP_ID 
    WHERE (th.USER_PERIOD_ID IN (13)) 
     AND (th.MOP_ID IN (1)) 
    GROUP BY ms.MOP_desc 
)t 

Answer 1

因爲從UNION ED結果查詢是一個行集，您已將別名t設置爲 - ms別名不再適用：

SELECT SUM(Amount) AS TotalAmount, t.MOP_desc 
FROM 
(
... 
)t 

如果這真的是第二步SUM步驟，您還需要一個外部GROUP BY子句。

Answer 2

當您從一個子查詢，而不是表中選擇，從子查詢中的列名不暴露於外部選擇

使用

SELECT SUM(Amount) AS TotalAmount, mop 
FROM 
(
    SELECT SUM(hd.delivery_value) AS Amount, ms.MOP_desc as mop 
    FROM TRANSACTION_HEADER AS th 
     INNER JOIN TRANSACTION_DETAIL AS td 
...