Question

我有一张商店，订单，物品，订购数量和装运数量的表。我想按存储的唯一订单数创建一个摘要，其中发货数量少于订单中一个或多个项目的订购数量。例如：

Store   OrderID ItemID  Ordered Shipped  
A          1      1        5      5  
A          1      2        2      0  
A          2      5        6      4  
A          2      2        4      4  
B          1      6        2      2  
B          1      12       1      1  
B          1      18       4      4  
B          2      8        2      2  
B          3      15       4      3

我想要以下结果：

Store   Orders  Good    Shorted  
A          2      0        2  
B          3      2        1

这表明商店A有2个订单，两个订单均未完全履行，而商店B有3个订单，其中2个订单已履行，还有1个未履行。

我正在寻找一种无需使用大量昂贵的子查询即可完成此操作的方法。有什么建议吗？

Answer 1

您可以使用视图或子查询来完成。这是我的观点解决方案：

Create view eachOrder as 
  select store, OrderID, sum(Ordered) as O, sum(Shipped) as s 
  from test 
  group by store, OrderID;

select store, 
    count(distinct orderid) as orders, 
    sum(case when o <= s then 1 else 0 end) as good,
    sum(case when o > s then 1 else 0 end) as shorted  
  from eachOrder 
  group by store;

这是我作为子查询的解决方案：

select
  store,
  count(distinct orderid) as orders,
  sum(case when o <= s then 1 else 0 end) as good,
  sum(case when o > s then 1 else 0 end) as shorted 
  from (select store, OrderID, 
          sum(Ordered) as O, 
          sum(Shipped) as s 
        from test 
        group by store, OrderID
      ) as EachOrder
  group by store;

您可以看到两种解决方案here https://paiza.io/projects/_0nkAIwfT2mzYKoehol0KA?language=mysql

Answer 2

使用子查询

    select t.Store,t.Orders,good,shorted from
(select  Store,count(*) as Orders
     from
     (select distinct Store,OrderID
    from table
     ) a group  by Store
) t
     join
     ( select store,
sum(case when ordered < shipped then 1  else 0 end) as good,
  sum(case when ordered > shipped then 1 else 0 end) as shorted 
from my_table group by store
     ) b on t.store=b.store

Answer 3

只需计算一个案例：

SELECT
  store,
  Count(DISTINCT orderid) AS orders,
  Sum(DISTINCT CASE WHEN ordered <= shipped THEN orderid END) AS good,
  Sum(DISTINCT CASE WHEN ordered > shipped THEN orderid END) AS shorted 
FROM my_table
GROUP BY store

或将三个不同的计数减少为两个：

SELECT store, orders, good, orders - good AS shorted
FROM
 (
   SELECT
     store,
     Count(DISTINCT orderid) AS orders,
     Sum(DISTINCT CASE WHEN ordered <= shipped THEN orderid END) AS good
   FROM my_table
   GROUP BY store
 ) AS dt

计算聚合函数中的不同值

3 个答案: