SQL Server Reporting Services中的平均值，中位數，模式

Question

是否可以計算一列數據的平均值，中位數，模式，標準偏差等？

一般來說，是否可以在SQL Server Reporting Services中進行這些類型的數學計算？

如果是這樣，該怎麼辦？

Answer 1

這裏是Median()從Report Design Tips and Tricks ...

方案1

1：在報表設計器，打開報告屬性對話框，然後單擊代碼選項卡。定義一個數組，一個接受一個值並將其添加到數組的函數，以及一個計算數組中值的函數;

Dim values As New SystemCollections.ArrayList 

Function AddValue(newValue As Decimal) As Decimal 
    values.Add(newValue) 
    AddValue = newValue 
End Function 

Function GetMedian() As Decimal 
    Dim count As Integer = values.Count 
    If (count > 0) 
     values.Sort() 
     GetMedian = values(count\2) 
    End If 
End Function 

2：將函數的調用放入聚合中，並將其添加到詳細信息行中的表達式中。

=Max(Code.AddValue(Fields!field.Name)) 

3：從表中的頁腳文本框，調入GetMedian（）來檢索值

=Code.GetMedian() 

Answer 2

下面是我收到模式適合年齡：

Declare @Temp Table(Id Int Identity(1,1), Data Decimal(10,5)) 

Insert into @Temp Select DATEDIFF (YY, EmployeeCustomTabFields.CustDOB, GETDATE()) - 
Case When (MONTH(EmployeeCustomTabFields.CustDOB)=MONTH(GETDATE()) AND DAY(EmployeeCustomTabFields.CustDOB) > DAY(GETDATE()) OR MONTH (EmployeeCustomTabFields.CustDOB) > MONTH (GETDATE())) 
Then 1 Else 0 End as Age 
From EM 
inner join EmployeeCustomTabFields on EmployeeCustomTabFields.Employee = EM.Employee 
Where EmployeeCustomTabFields.CustDepartment = '23 - Piping Design' and EM.Status = 'A' and EM.Type in ('A','B','C') 

Select Top 1 with ties DATA 
From @Temp 
Where DATA IS Not NULL 
Group By DATA 
Order By COUNT(*) DESC 

Answer 3

在@ Homer的回答中進行了擴展，下面的代碼可以用來獲取中位數和模式。我需要Integer的，但接受Decimal或Double將會是一個快速的改變。

Dim values As New System.Collections.Generic.List(Of Integer) 
Dim valueCounts As New System.Collections.Generic.Dictionary(Of Integer, Integer) 

Function AddValue(newValue As Integer) As Integer 
    values.Add(newValue) 
    AddValue = newValue 
    If Not valueCounts.ContainsKey(newValue) Then 
     valueCounts.item(newValue) = 1 
    Else 
     valueCounts.item(newValue) += 1 
    End If 
End Function 

Function GetMedian() As Double 
    Dim count As Integer = values.Count 
    If count = 0 Then 
     Return 0 
    Else 
     values.Sort() 
     If count Mod 2 = 1 Then 
      Return values(CInt((count/2) - 0.5)) 
     Else 
      Dim index1 As Integer = count \ 2 
      Dim index2 As Integer = index1 - 1 

      Dim value1, value2 As Integer 
      value1 = values(index1) 
      value2 = values(index2) 

      Return (value1 + value2)/2 
     End If 
    End If 
End Function 

Function GetMode() As String 
    Dim max As Integer = 0 
    For Each v As Integer In valueCounts.Values 
     If v > max Then 
      max = v 
     End If 
    Next v 

    Dim maxCount As Integer = 0 
    Dim retValue As String = "" 
    For Each vcKvp As System.Collections.Generic.KeyValuePair(Of Integer, Integer) In valueCounts 
     If vcKvp.Value = max Then 
      maxCount += 1 
      If Not String.IsNullOrEmpty(retValue) Then 
       retValue &= ", " 
      End If 
      retValue &= vcKvp.Key 
     End If 
    Next vcKvp 

    If maxCount = valueCounts.Count Then 
     Return "N/A" 
    End If 

    Return retValue 
End Function