题目：请你写一个sql语句查询各个岗位分数升序排列之后的中位数位置的范围，并且按job升序排序，

思路：

函数：floor(），功能：向下取整数 得到为偶数时中间数开始的数（方法二）

case when 1 then 2 else 3 end ，解释：当1时，就得到2，否则得到3(方法一)

答案：

方法一：

select g.job, case when count(score) % 2 = 0 then ceiling(count()/2) else ceiling(count()/2) end as start, case when count(score) % 2 = 0 then ceiling(count()/2 + 1) else ceiling(count()/2) end as end from grade as g group by g.job order by g.job

方法二：

select g.job,

floor((count(*) + 1)/2) as start,

floor((count(*) + 2)/2) as end

from grade as g

group by g.job

order by g.job