级联查询 where store_id in(select store_id from store_staff where user_id = #{user_id})

判断赋值 (case when (select use_name from users s where use_id = p.op_name)is not NULL then (select use_name from users s where use_id = p.op_name) else p.op_name end)op_name, in_datetime,

模糊查找 in_datetime LIKE CONCAT (‘" + data + "%‘)"

一些mysql语句