需求是这样的：需要找出没有发任务的店铺是哪些。好让客服去联系他们，询问情况。

每个商家可以有N个店铺，每个店铺可以放N个任务，一个任务会生成N个任务订单，会员接到任务去完成

SELECT *
FROM `keke_w_mall_shop`
WHERE shopid NOT
IN (

SELECT shopid
FROM (

SELECT shopid, kk, uid
FROM (

SELECT DISTINCT a.shopid, count( 1 ) AS kk, a.uid
FROM `keke_w_mall_shop` AS a
LEFT JOIN `keke_w_task_work` AS b
USING ( shopid )
WHERE b.op_status >0
GROUP BY b.shopid
) AS a
) AS p
WHERE 1 =1
)

用到了唯一，和子查询，和左关联查询