mysql刪除子查詢不能正常工作的查詢

Question

我嘗試創建mysql事件應該刪除重複的表的行。

這是我的查詢

DELETE FROM locations 
WHERE id NOT IN (SELECT id 
       FROM locations 
       GROUP BY acc_id,`date`) 

我得到這個錯誤：

Error Code: 1093 
You can't specify target table 'locations' for update in FROM clause. 

如何更改查詢，使其工作？

Answer 1

在MySQL中，您無法從您正在選擇的同一張表中刪除。但是，你可以欺騙的MySQL與另一個子查詢

DELETE FROM locations 
WHERE id NOT IN 
(
    select * from 
    (
     SELECT id 
     FROM locations 
     GROUP BY acc_id, `date` 
) x 
) 

Answer 2

儘量提供您的子查詢中的自定義的別名，你不能直接指定更新同桌/刪除

DELETE FROM locations 
WHERE id NOT IN (
SELECT new_table.id FROM (
SELECT id 
FROM locations 
GROUP BY acc_id,`date` 
) new_table  
)