使用子查询在同一表上左联接

Question

select *
from (select *
    from TableO to
    where to.week='22'
    and to.year='2018'
    ) as O 
   left join TableO lto on O.user_id=lto.user_id
where O.user_id IS NULL

此查询出现问题。谁能看到错误所在？

我正在尝试在同一张桌子上保留联接，试图找到这一部分：

Answer 1

这将为您提供在2018年订购的user_id，但自第22周以来没有订购

select user_id 
from   TableO
where  year = 2018
group by user_id 
having max(week) <= 22

Answer 2

SELECT userid FROM TABLE1 
EXCEPT 
(SELECT userid FROM Table2 INTERSECT SELECT userid from table2)