mysql - MySQL：从 IN 中删除

Question

我知道这是一个简单的语法问题。尝试从子查询中删除所有用户：

delete from users
where id IN (

select u.id
from users u 
where not exists (select * from stickies i where i.user_id = u.id) 
group by u.email 
having count(*) > 1

)

收到此错误：

error : You can't specify target table 'users' for update in FROM clause

子查询工作正常（返回用户 ID 列表）。

Answer 1

DELETE u.*
FROM users u JOIN (
    SELECT u.id
    FROM users u LEFT JOIN stickies i ON i.user_id = u.id
    WHERE i.user_id IS NULL
    GROUP BY u.email 
    HAVING COUNT(*) > 1
  ) r ON r.id = r.id

注意：在内部查询中，您按电子邮件分组，但选择了一个用户 ID。这可能会返回不确定的结果。