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Title: mysql 查询x表posts字段,删除重复的值&同一日的数据只保留posts最大的那条  
  This topic was added by com at 2024-11-22 11:53 移动 
 
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mysql 查询x表posts字段,删除重复的值&同一日的数据只保留posts最大的那条

mysql 查询x表posts字段,删除重复的值

DELETE FROM X
WHERE id NOT IN (
    SELECT * FROM (
        SELECT MAX(id)
        FROM X
        GROUP BY posts
    ) AS temp
);
day字段类型为timestamp,同一日的数据只保留posts最大的那条。

DELETE t1
FROM X t1
JOIN (
    SELECT DATE(day) AS date, MAX(posts) AS max_posts
    FROM X
    GROUP BY DATE(day)
) t2 ON DATE(t1.day) = t2.date AND t1.posts < t2.max_posts;
[ 本帖最后由 sky999 于 2023-7-16 15:01 编辑 ]

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