如何对数据组进行排序？

Question

鉴于以下情况，并负责按每组内的 SUM（体积）对原始数据进行排名：

group_id    volume
1           2
1           3
2           5
3           1
3           3

如何获得以下内容？

group_id    volume  group_volume    rank
1           2       5               1
1           3       5               1
2           5       5               2
3           1       4               3
3           3       4               3

我可以轻松获得group_volume，但我正在努力解决如何打破排名的关系，而不是在单独的子查询中按 + 排名分组并加入。

SELECT *
, SUM(volume) OVER (PARTITION BY group_id) AS grouped_volume
, ... AS rank
FROM groups

Answer 1

使用 CTE 和 Dense_rank

WITH CTE1 AS (SELECT group_id, volume, 
              sum(volume) over(partition by group_id) group_volume
from table1)
SELECT A.*, dense_rank() over( order by  group_id, group_volume) rank FROM CTE1 A;

Answer 2

为此使用两级窗口函数：

select g.*,
       dense_rank() over (order by group_volume desc, group_id) as rank
from (select g.*,
             sum(volume) over (partition by group_id) as group_volume
      from groups g
     ) g;

不需要JOIN。