mysql - 选择 MySQL 中出现次数最多的值

Question

我正在寻找一种方法来选择出现次数最多的值，例如在每个主题中发帖最多的人；

SELECT MOST_OCCURRING(user_id) FROM thread_posts GROUP BY thread_id

有什么好的方法吗？

Answer 1

如果你想在每个线程的基础上进行计数，我认为你可以使用嵌套查询；先按线程分组，再按用户分组:

SELECT thread_id AS tid,
    (SELECT user_id FROM thread_posts 
        WHERE thread_id = tid 
        GROUP BY user_id
        ORDER BY COUNT(*) DESC
        LIMIT 0,1) AS topUser
FROM thread_posts
GROUP BY thread_id