Question

我想获得平均值

我有下表：

| ClientName | MemberName | TotalAmountSpent | PercentAmountSpent|
|-----Palace--- |---------John---- |-----------376.26------ |------------???------------ |
|-----Palace--- |--------Adem---- |-----------646.83------ |------------???------------ |
|----Pizzeria--- |---------Zoey----- |-----------10.00-------- |------------???------------ |

这是我到目前为止所做的：

SELECT  c.ClientName
        ,m.Mem_Name     


        ,Sum(mv.AmountSpent) as TotalAmountSpent
        ,Sum(mv.AmountSpent)/ *100 as PercentAmountSpent


FROM Client c

JOIN MemberVisits mv
On c.ClientId = mv.RestaurantId 
JOIN Member m
On m.Mem_ID = mv.MemberId

GROUP by ClientName, m.Mem_Name

ORDER by ClientName

公式为：(Total Amount Spent / total business sales) * 100

例如：johns percentamountspent应为(376.26/ (376.26 + 646.83)) * 100

如何修复此行Sum(mv.AmountSpent)/ /*Something here */ *100 as PercentAmountSpent以获得正确的输出？

由于

Answer 1

你可以这样做：

http://sqlfiddle.com/#!6/cf953/4

create table test (ClientName varchar(50), MemberName varchar(50), TotalAmountSpent float)
insert into test (ClientName, MemberName, TotalAmountSpent)
select 'Palace', 'John', 376.26
union all select 'Palace', 'Adem', 646.83
union all select 'Pizzeria', 'Zoey', 10

select t.ClientName, 
    t.MemberName, 
    t.TotalAmountSpent, 
    (t.TotalAmountSpent / groupedClientName.totalAmountSpent * 100) as percentAmountSpent
from test t
inner join (
    -- this subquery is used to get the total amount per "Client", which then can be used in the outer query to get a per member contribution percent
    select ClientName, sum(totalAmountSpent) as totalAmountSpent
    from  test
    group by ClientName
  ) groupedClientName on t.ClientName = groupedClientName.ClientName

Answer 2

您可以使用子查询（以避免在计算中使用多个SUM），并使用另一个子查询上的内部联接来获取totalBusinessSales（看起来像是RestaurantId的amountSpent之和）

select 
    ClientName
    MemName,
    totalAmountSpent,
    sumAmountSpent / totalBusinessSales * 100 as percentAmountSpent
    from

    (select c.ClientName,
            m.Mem_Name,
           sum(mv.AmountSpent) as totalAmountSpent,
           sum(s.TotalBusinessSales) as totalBusinessSales
    from Client c
    join MemberVisits mv on c.ClientId = mv.RestaurantId 
    join Member m on m.Mem_ID = mv.MemberId 
    join (select RestaurantId, sum(amountSpent) as TotalBusinessSales
          from MemberVisits
          group by RestaurantId) s
        on s.RestaurantId = c.ClientId
    group by t.ClientName, m.Mem_Name) i

没有第一级子查询，你会有

select c.ClientName,
       m.Mem_Name,
       sum(mv.AmountSpent) as totalAmountSpent,
       sum (mv.AmountSpent) / sum(s.TotalBusinessSales) * 100  as percentAmountSpent
from Client c
join MemberVisits mv on c.ClientId = mv.RestaurantId 
join Member m on m.Mem_ID = mv.MemberId 
join (  select RestaurantId, sum(amountSpent) as TotalBusinessSales
        from MemberVisits
        group by RestaurantId) s
            on s.RestaurantId = c.ClientId
group by t.ClientName, m.Mem_Name

添加多个行条目然后划分sql

2 个答案: