sql - 按分组运行总和

Question

我有这个查询

SELECT  NAME, OTHER_NAME, COUNT(NAME)
FROM ETHNICITY
GROUP BY NAME,OTHER_NAME

我想在该列上other_name或name该列中添加一个运行总和。

例如，如果有 3x 非裔美国人和 2x name= "other" 和 other_name = "jewish" 我想给它 3 和 2 作为计数并在遍历时将它们相加

有什么想法可以增加它以添加它吗？谢谢。

Answer 1

我更喜欢使用子查询来做到这一点：

select t.name, t.other_name, t.cnt,
       sum(cnt) over (order by name) as cumecnt
from (SELECT  NAME, OTHER_NAME, COUNT(NAME) as cnt
      FROM ETHNICITY
      GROUP BY NAME,OTHER_NAME
     ) t

这假设您需要按name.

分析函数中的 order by 进行累积和。这是标准语法，Postgres 和 SQL Server 2012 也支持。

以下可能也有效

select name, other_name, count(name) as cnt,
       sum(count(name)) over (order by name)
from ethnicity
group by name, other_name

我发现这更难阅读（sum(count())有点刺耳）并且可能更容易出错。我没有在 Oracle 上尝试过这种语法；它在 SQL Server 2012 中工作。

Answer 2

sum() ... over()在 Oracle 中，可以使用窗口函数轻松完成运行总和：

select  name
,       other_name
,       name_count
,       sum(name_count) over(
            order by name, other_name) as running
from    (
        select  name
        ,       other_name
        ,       count(name) as name_count
        from    ethnicity
        group by 
                name
        ,       other_name
        order by
                name
        ,       other_name
        ) subqueryalias

SQL Fiddle 上的示例

Answer 3

查看分组集，让您汇总总数。

虽然不确定这是你所追求的......

SELECT  NAME, OTHER_NAME, COUNT(NAME)
FROM ETHNICITY
GROUP BY GROUPING SETS ((NAME,OTHER_NAME), (Name), ())

抱歉 ID10T 错误...分组集不需要第二个聚合，计数将自行完成：

所以这个数据：

Name   Other_Name
A       B
A       C
A       D
B       E
B       F
B       G
C       H
C       I
C       J

结果是

Name   Other_Name   CNT(Name)
A      B           1
A      C           1
A      D           1
A                  3
B      E           1
B      F           1
B      G           1
B                  3
C      H           1
C      I           1
C      J           1
C                  3
                   9