尝试计算订单总数和每月唯一客户

编程问答 2022-05-22

问题描述

我正在尝试获取订单总量，以及 30 天内的唯一客户数量。

我有这张桌子：

order_id、order_date、order_country、customer_id。

(1,'2021/03/04','SWE',1),(2,'2021/03/01',(3,'DK',3),(4,(5,'2021/03/03','nor',2),(6,'2021/02/27',(7,'2020/12/30','Ger',4);

我尝试过这样的事情：

SELECT order_date,COUNT(order_id) as orderAmount,COUNT(distinct customer_id) as customerAmount 
  FROM orders
 WHERE order_date BETWEEN Now() - INTERVAL 30 DAY AND Now() 
 GROUP 
    BY order_date

这将获得每个日期的订单总数，这正是我想要的。但它只计算每个日期而不是每月的唯一客户，因此同一客户出现多次。我已经尝试了这个 sql 脚本的小变化，但不能让它工作。

解决方法

请检查这是否是您想要的答案。

架构（MySQL v5.5）

create table orders (order_id int,order_date date,order_country varchar(10),customer_id int);
insert into orders values(1,'2021/03/04','SWE',1);
insert into orders values(2,'2021/03/01',1);
insert into orders values(3,'DK',3);
insert into orders values(4,3);
insert into orders values(5,'2021/03/03','NOR',2);
insert into orders values(6,'2021/02/27',3);
insert into orders values(7,'2020/12/30','Ger',4);

查询 #1

SELECT 
      o.order_date,COUNT(order_id) as orderAmount,coalesce(max(Customer_Count),0) as customerAmount 
  FROM orders o left join (select order_date,count(distinct customer_id)Customer_Count from orders o where 
 not exists (select customer_id from orders oa where o.customer_id=oa.customer_id and oa.order_date<o.order_date
            and oa.order_date > now() - INTERVAL 30 DAY  )
 group by order_date) oc on o.order_date=oc.order_date
 WHERE o.order_date BETWEEN NOW() - INTERVAL 30 DAY AND NOW() 
 group by o.order_date
 order by o.order_date;
订单日期 订单金额 客户金额
2021-02-27 1 1
2021-03-01 3 1
2021-03-03 1 1
2021-03-04 1 0

View on DB Fiddle

,

只计算客户第一次出现的时间：

SELECT order_date,COUNT(*) as num_orders,COUNT(DISTINCT customer_id) as distinct_customers_on_day,SUM(SUM(seqnum = 1)) OVER (ORDER BY order_date) as running_distinct_customers
FROM (SELECT o.*,ROW_NUMBER() OVER (PARTITION BY customer_id ORDER BY order_date) as seqnum
      FROM orders o
      WHERE o.order_date BETWEEN NOW() - INTERVAL 30 DAY AND NOW() 
     ) o
GROUP BY order_date;

Here 是一个 dbfiddle。

mysqlscriptsqlsql