Sql Server 2012中一个查询的平均值和中位数

Question

我的表中有以下数据:

SELECT category, value FROM test

 
| category | value |
+----------+-------+
|    1     |   1   | 
|    1     |   3   |
|    1     |   4   |
|    1     |   8   |

现在我正在使用两个单独的查询.

1. 要获得平均值:

     SELECT category, avg(value) as Average
       FROM test
   GROUP BY category
   

    
    | category | value |
    +----------+-------+
    |    1     |   4   | 
    

2. 获得中位数:

   SELECT DISTINCT category, 
                   PERCENTILE_CONT(0.5) 
                      WITHIN GROUP (ORDER BY value) 
                      OVER (partition BY category) AS Median
              FROM test
   

    
    | category | value |
    +----------+-------+
    |    1     |  3.5  | 
    

有没有办法在一个查询中合并它们？

注意:我知道我也可以使用两个子查询获得中位数,但我更喜欢使用PERCENTILE_CONT函数来获取它.

Answer 1

AVG也是一个窗口功能:

select 
distinct
category,
avg(value) over (partition by category) as average,
PERCENTILE_CONT(0.5) 
                   WITHIN GROUP (ORDER BY value) 
                   OVER (partition BY category) AS Median
                   from test