主题：如何计算平均每次购买金额

Dim count As Integer = DataTables("原始数据").GetUniqueValues("姓名 = 'xxx'", "日期").count

Dim sum As Double = DataTables("原始数据").Compute("sum(金额)", "姓名 = 'xxx'")

msgbox(sum / count)

Select Case e.DataCol.Name

    Case "最后购买日期"

        If e.DataRow.IsNull("最后购买日期") Then

            e.DataRow("近度") = Nothing

        Else

            Dim  y,m,d As  Integer

            Dim dt1 As  Date =  e.DataRow("最后购买日期")

            Dim dt2 As  Date =  Date.Today

            DateYMD(dt1,dt2,y,m,d)

            e.DataRow("近度") = y * 12 + m

        End If

    Case "密度"

        If e.DataRow.IsNull("密度") = False AndAlso e.DataRow("密度") >= 0 Then

            Select Case e.DataRow("密度")

                Case 0 To 2

                    e.DataRow("密度级别") = 1

                Case 3 To 5

                    e.DataRow("密度级别") = 2

                Case Else

                    e.DataRow("密度级别") = 3

            End Select

        End If

    Case "姓名"

Dim Filter As String = "[姓名] = '" & e.NewValue & "'"

        If e.DataRow.Isnull("姓名") = False

            Dim pl As String = DataTables("原始数据").GetComboListString("日期", filter & " and 日期 not is null")

            e.DataRow("密度") = pl.Length - pl.Replace("|","").Length +1

        Else

            e.DataRow("密度") = Nothing

        End If        

        

        If e.DataRow.Isnull("姓名") = False

            Dim pl As String = DataTables("原始数据").GetComboListString("品类", filter & " and 品类 not is null")

            e.DataRow("宽度") = pl.Length - pl.Replace("|","").Length +1

        Else

            e.DataRow("宽度") = Nothing

        End If

        

        e.DataRow("最后购买日期") = DataTables("原始数据").Compute("Max(日期)", Filter)

        

        Dim count As Integer = DataTables("原始数据").GetUniqueValues(Filter, "日期").count

        Dim sum As Double = DataTables("原始数据").Compute("sum(金额)", Filter)

        e.DataRow("平均每次购买金额") = sum / count

End Select