使用 group by -SQL (Impala) 计算两个表之间的百分比

Question

我正在 Impala (Cloudera) 上工作，我有两个 tables，Customers 和 Arrangements。客户 table 有以下列：

customercrs | customertype| 
------------+-------------+
 1000       | NP          |  
 100000     | NP          |   
 100001     | NP          |  
 100002     | GROUP       |  
 100023     | GROUP       |
 100024     | INDIRECT    |

排列table：

customercrs | arrangementid| 
------------+--------------+
 1000       | 11000000361  |  
 100000     | 11000000370  |  
 100000     | 11000000434  |
 100000     | 11000000426  |
 100001     | 11000000418  | 
 100001     | 11000000400  |
 100001     | 11000000396  |
 100001     | 11000000388  |
 100002     | 11000000591  |  
 100002     | 11000000582  |
 100023     | 11000000574  |
 100024     | 11000000566  |
 100024     | 11000000558  |

我想计算每种客户类型的安排百分比。类似于：

customertype | percentage  |
-------------+-------------+
 NP          | 62%         |
 GROUP       | 23%         |
 INDIRECT    | 15%         |

我尝试了以下 sql 查询，但没有成功。有什么想法吗？

select customertype, count(*)/(select count(*) from arrangements)
from customers as a, arrangements_sample as b
where a.customercrs = b.customercrs
group by a.customertype

谢谢！！！

Answer 1

我会将 window 函数与显式 JOIN 一起使用，但是，您的解决方案似乎没问题（对于 Impala 以外的其他 DBMS）

select customertype, 
       (count(*) * 100) / sum(count(*)) over () percentage
from customers as a
join arrangements_sample as b on a.customercrs = b.customercrs
group by a.customertype

Answer 2

尝试加入subselect，我用max作为分组函数，但是min或avg也可以...

select customertype, count(*)/max(c.total)
from customers as a, arrangements_sample as b, (select count(*) as total from 
arrangements) as c
where a.customercrs = b.customercrs
group by a.customertype

Answer 3

您需要每个客户类型参与安排的总数。所以请尝试以下查询。

select main.customertype,cast((cast(main.participation as decimal(10,2))/main.total)*100 as decimal(10,2) ) 作为参与 from (select customertype,COUNT(1) as participation,(select COUNT(1) from arrangements) as total from 安排 a b.customercrs = a.customercrs 上的内部加入客户 b 按 b.customertype) 分组为主要

使用 group by -SQL (Impala) 计算两个表之间的百分比

Calculate percentage between two tables with group by -SQL (Impala)

sql

impala