在 Case 语句中求和

Question

我正在尝试在满足条件时计算字段。我已经玩了几个小时了，但没有运气:(。

所以我需要找到并计算每个月的保证金。我这样做是为了销售，这很简单

SUM(CASE when CalendarMonth = 1 then TotalSales else 0 end) as 'January',

但是，在尝试计算保证金时，我经常会遇到错误 '无法对包含聚合或子查询的表达式执行聚合函数。'

我是不是走错了路？

    Declare @Sales numeric, @Cost numeric, @Margin Numeric

    Set @Sales = (Select SUM(TotalSales)
            From SalesAnalysis2)

    Set @Cost = (Select SUM(TotalCost)
            From SalesAnalysis2)

    Set @Margin = ((@Sales - @Cost) / @Sales)

    Select distinct

    Case CalendarMonth when 1 then @Margin else 0 end as 'January',
    Case CalendarMonth when 2 then @Margin else 0 end as 'Febuary',
    Case CalendarMonth when 3 then @Margin else 0 end as 'March',
    Case CalendarMonth when 4 then @Margin else 0 end as 'April',
    Case CalendarMonth when 5 then @Margin else 0 end as 'May',
    Case CalendarMonth when 6 then @Margin else 0 end as 'June',
    Case CalendarMonth when 7 then @Margin else 0 end as 'July',
    Case CalendarMonth when 8 then @Margin else 0 end as 'August',
    Case CalendarMonth when 9 then @Margin else 0 end as 'September',
    Case CalendarMonth when 10 then @Margin else 0 end as 'Octocber',
    Case CalendarMonth when 11 then @Margin else 0 end as 'November',
    Case CalendarMonth when 12 then @Margin else 0 end as 'December'

    From SalesAnalysis2

    where CustomerID = 2829 and BranchID = 0 and CalendarYear = Year(Getdate())

这是我做的销售，我需要使用相同的格式来显示利润。 但是同一张表中没有margin字段，需要计算 Sales Example

Answer 1

您需要为每个月执行保证金计算，而不是使用您只设置一次的变量。此外，要将 case 语句用作枢轴，您还需要一个 MAX 聚合来减少返回的行数。否则，您每个月都会得到一行，每行中只有一列的值不是 0。

WITH p AS
  (
    SELECT      CalendarMonth,
                TotalSales = SUM( TotalSales ),
                TotalCost = SUM( TotalCost ),
                Profit = SUM( TotalSales - TotalCost )
      FROM      SalesAnalysis2
      GROUP BY  CalendarMonth
  )
  SELECT
    MAX(CASE CalendarMonth when 1 then p.Profit/p.TotalSales else 0 END) as 'January',
    MAX(Case CalendarMonth when 2 then p.Profit/p.TotalSales else 0 END) as 'Febuary',
    MAX(Case CalendarMonth when 3 then p.Profit/p.TotalSales else 0 END) as 'March',
    MAX(Case CalendarMonth when 4 then p.Profit/p.TotalSales else 0 END) as 'April',
    MAX(Case CalendarMonth when 5 then p.Profit/p.TotalSales else 0 END) as 'May',
    MAX(Case CalendarMonth when 6 then p.Profit/p.TotalSales else 0 END) as 'June',
    MAX(Case CalendarMonth when 7 then p.Profit/p.TotalSales else 0 END) as 'July',
    MAX(Case CalendarMonth when 8 then p.Profit/p.TotalSales else 0 END) as 'August',
    MAX(Case CalendarMonth when 9 then p.Profit/p.TotalSales else 0 END) as 'September',
    MAX(Case CalendarMonth when 10 then p.Profit/p.TotalSales else 0 END) as 'Octocber',
    MAX(Case CalendarMonth when 11 then p.Profit/p.TotalSales else 0 END) as 'November',
    MAX(Case CalendarMonth when 12 then p.Profit/p.TotalSales else 0 END) as 'December'
  FROM    p

由于您没有提供任何架构或数据，因此您需要对其进行修改以适合您的数据。它可能无法为您写入的数据提供准确的结果，但它至少应该为每个月返回不同的值，并有望让您更接近所需的解决方案。

Answer 2

你想要一个sum()：

Select sum(Case CalendarMonth when 1 then @Margin else 0 end) as January,
       sum(Case CalendarMonth when 2 then @Margin else 0 end) as February,
       . . .
From SalesAnalysis2
where CustomerID = 2829 and BranchID = 0 and
      CalendarYear = Year(Getdate())

Answer 3

请尝试：

Declare @Sales numeric, @Cost numeric, @Margin Numeric

Set @Sales = (Select SUM(TotalSales)
        From SalesAnalysis2)

Set @Cost = (Select SUM(TotalCost)
        From SalesAnalysis2)

Set @Margin = ((@Sales - @Cost) / @Sales)

Select distinct

Case Month(YourDateColumn) =1 then @Margin else 0 end as 'January',
Case Month(YourDateColumn) =2 then @Margin else 0 end as 'Febuary',
Case Month(YourDateColumn) =3 then @Margin else 0 end as 'March',
Case Month(YourDateColumn) =4 then @Margin else 0 end as 'April',
Case Month(YourDateColumn) =5 then @Margin else 0 end as 'May',
Case Month(YourDateColumn) =6 then @Margin else 0 end as 'June',
Case Month(YourDateColumn) =7 then @Margin else 0 end as 'July',
Case Month(YourDateColumn) =8 then @Margin else 0 end as 'August',
Case Month(YourDateColumn) =9 then @Margin else 0 end as 'September',
Case Month(YourDateColumn) =10 then @Margin else 0 end as 'Octocber',
Case Month(YourDateColumn) =11 then @Margin else 0 end as 'November',
Case Month(YourDateColumn) =12 then @Margin else 0 end as 'December'

From SalesAnalysis2

where CustomerID = 2829 and BranchID = 0 and CalendarYear = Year(Getdate())