Question

我是MySQL新手，在转换SQL语句时遇到问题，如果可能的话，我希望得到一些帮助。

故障是我需要能够根据上次登录日期从一个表中删除项目，遗憾的是我无法控制表设计（这是有缺陷的）并且必须将characterID与characterUID和LastLogin进行比较date，以便从另一个只删除charcaterID（非唯一）对象的表中删除项目。

这是我到目前为止所拥有的

DELETE FROM object_data WHERE CharacterID IN (
    SELECT CharacterID FROM object_data 
    WHERE CharacterID IN (
        SELECT CharacterID FROM character_data
            WHERE LastLogin < DATE_SUB(NOW(), INTERVAL 30 DAY)
            AND PlayerUID NOT IN (
                SELECT PlayerUID FROM character_data 
                    WHERE LastLogin > DATE_SUB(NOW(), INTERVAL 30 DAY))))

我得到的错误是1093.你不能从FROM子句中的update更新目标表'object_date'。

有什么想法吗？

Answer 1

立即尝试：

DELETE FROM object_data WHERE CharacterID IN (
    SELECT CharacterID FROM  (
        SELECT CharacterID FROM character_data
            WHERE LastLogin < DATE_SUB(NOW(), INTERVAL 30 DAY)
            AND PlayerUID NOT IN (
                SELECT PlayerUID FROM character_data 
                    WHERE LastLogin > DATE_SUB(NOW(), INTERVAL 30 DAY)))y)

Answer 2

如果您没有为子查询表名称命名

，有时会使用SQL barfs

DELETE FROM object_data 
WHERE CharacterID IN 
(
  SELECT CharacterID 
  FROM object_data 
  WHERE CharacterID IN 
  (
    SELECT CharacterID 
    FROM character_data
    WHERE LastLogin < DATE_SUB(NOW(), INTERVAL 30 DAY)
    AND PlayerUID NOT IN 
    (
       SELECT PlayerUID 
       FROM character_data 
       WHERE LastLogin > DATE_SUB(NOW(), INTERVAL 30 DAY)  
    ) AS t1
  ) AS t2
) AS t3

基于唯一ID和非唯一ID从mysql中删除多个记录

2 个答案: