錯誤1248：「每一個派生的表必須有它自己的別名」

Question

我試圖運行此查詢：

SELECT DISTINCT col1 
FROM 
    (
    SELECT CONCAT(retailerId,'_recharge') FROM retailerinformation 
    WHERE Channel='videocon' AND retailerId='kioskpb20130909045617' 
) 

但運行每次我得到這個錯誤：

Error Code : 1248 Every derived table must have its own alias 

Answer 1

你的錯誤非常明顯。創建一個別名：

SELECT DISTINCT 
    col1 
FROM 
    (select concat(retailerId,'_recharge') from retailerinformation where Channel='videocon' and retailerId='kioskpb20130909045617') AS tmp_table 

提示：如果你嘗試瞭解錯誤，而不是僅僅看他們 - 這將是成功的故事。

Answer 2

試試這個版本：

select DISTINCT col1 from 
(select concat(retailerId,'_recharge') from retailerinformation 
    where Channel='videocon' and retailerId='kioskpb20130909045617') as retailerino 

注意你的子查詢的別名。

Answer 3

這將工作：

SELECT 
DISTINCT col1 
FROM (
    SELECT concat(retailerId,'_recharge') 
    FROM retailerinformation where Channel='videocon' and retailerId='kioskpb20130909045617' 
    ) AS alias 

Answer 4

除了添加別名的子查詢，呼籲外部查詢列應在子查詢存在。在這種情況下，col1應該存在於子查詢中。這就是說，這應該是工作

SELECT DISTINCT col1 
FROM 
    (
    SELECT CONCAT(retailerId,'_recharge') col1 FROM retailerinformation 
    WHERE Channel='videocon' AND retailerId='kioskpb20130909045617' 
) sub