mysql - 如何从子查询中选择更多行

Question

当我尝试运行此查询时：

 select * FROM `activity` 
 WHERE user_id = 1
 AND activity_id NOT LIKE (select activity_id from activity where user_id = 1 ORDER BY activity_id DESC LIMIT 8)

我收到以下错误：

 Subquery returns more than 1 row

我怎么解决这个问题？我想从表中选择活动 ID，不包括某个用户的最新 8 个活动 ID。

Answer 1

NOT LIKE 期望一个表达式或一个值来比较，而不是一个结果集。将 NOT LIKE 更改为 NOT IN

试试这个：

    SELECT * FROM `activity` 
             WHERE user_id = 1 AND activity_id NOT IN (
                     SELECT activity_id FROM activity WHERE user_id = 1 
                                        ORDER BY activity_id DESC LIMIT 8)

Answer 2

通过这样做解决了它：

                $sql2 = "DELETE t1.*
                        FROM activity t1
                        left join (select activity_id from activity where user_id = '".$row['user_id']."' ORDER BY activity_id DESC LIMIT 8) t2
                        on (t1.activity_id = t2.activity_id)
                        where t2.activity_id is null
                        and t1.user_id = '".$row['user_id']."'";