SQL TVM或年金函数PV、FV、NPER、利率、PMT_Sql_Sql Server_Sql Server 2008

SQL TVM或年金函数PV、FV、NPER、利率、PMT

sql sql-server sql-server-2008

SQL TVM或年金函数PV、FV、NPER、利率、PMT,sql,sql-server,sql-server-2008,Sql,Sql Server,Sql Server 2008,我正在尝试收集一些UDF，作为一名优秀的程序员，我更喜欢CRTL+C、CRTL+V方法。而且我的数学成绩不是100%。基本上，我希望模拟excel中的函数：NPER、RATE、PV、FV、PMT，由于某些原因，这些函数很难找到，但我不能相信有人没有它们。我使用的是SQLServer2008，所以如果我有企业或BI，可能会添加它们，这就是为什么没有人要求添加它们的原因。下面是一个我发现似乎对PMT很有效的方法经过长时间的搜索，感谢Jeff Orris和Lad2025。我得出结论，a CLR是最好

我正在尝试收集一些UDF，作为一名优秀的程序员，我更喜欢CRTL+C、CRTL+V方法。而且我的数学成绩不是100%。基本上，我希望模拟excel中的函数：NPER、RATE、PV、FV、PMT，由于某些原因，这些函数很难找到，但我不能相信有人没有它们。我使用的是SQLServer2008，所以如果我有企业或BI，可能会添加它们，这就是为什么没有人要求添加它们的原因。下面是一个我发现似乎对PMT很有效的方法

经过长时间的搜索，感谢Jeff Orris和Lad2025。我得出结论，a CLR是最好的方法。为了帮助其他SO用户，我现在将发布一些东西

首先。这是CLR的基本VB代码。要安装它，请按照对我的问题的评论进行操作

Imports System
Imports System.Data
Imports System.Data.SqlClient
Imports System.Data.SqlTypes
Imports Microsoft.SqlServer.Server


Partial Public Class ExcelFunctions
    <Microsoft.SqlServer.Server.SqlFunction(IsDeterministic:=True, IsPrecise:=True)> _
    Public Shared Function fPMT(ByVal Rate As Double, ByVal NPer As Double, ByVal PV As Double, Optional ByVal FV As Double = 0, Optional ByVal Type As Byte = 0) As SqlDouble
        Dim PMTS As Double

        If Type = 0 Then
            PMTS = Pmt(Rate, NPer, PV, FV, DueDate.EndOfPeriod)
        ElseIf Type = 1 Then
            PMTS = Pmt(Rate, NPer, PV, FV, DueDate.BegOfPeriod)
        End If

        Return New SqlDouble(PMTS)
    End Function
    <Microsoft.SqlServer.Server.SqlFunction(IsDeterministic:=True, IsPrecise:=True)> _
    Public Shared Function fNPER(ByVal Rate As Double, ByVal PMTS As Double, ByVal PV As Double, Optional ByVal FV As Double = 0, Optional ByVal Type As Byte = 0) As SqlDouble
        Dim NPERS As Double

        If Type = 0 Then
            NPERS = NPer(Rate, PMTS, PV, FV, DueDate.EndOfPeriod)
        ElseIf Type = 1 Then
            NPERS = NPer(Rate, PMTS, PV, FV, DueDate.BegOfPeriod)
        End If

        Return New SqlDouble(NPERS)
    End Function
    <Microsoft.SqlServer.Server.SqlFunction(IsDeterministic:=True, IsPrecise:=True)> _
    Public Shared Function fPV(ByVal Rate As Double, ByVal NPER As Double, ByVal PMTS As Double, Optional ByVal FV As Double = 0, Optional ByVal Type As Byte = 0) As SqlDouble
        Dim PVs As Double

        If Type = 0 Then
            PVs = PV(Rate, NPER, PMTS, FV, DueDate.EndOfPeriod)
        ElseIf Type = 1 Then
            PVs = PV(Rate, NPER, PMTS, FV, DueDate.BegOfPeriod)
        End If

        Return New SqlDouble(PVs)
    End Function
    <Microsoft.SqlServer.Server.SqlFunction(IsDeterministic:=True, IsPrecise:=True)> _
    Public Shared Function fFV(ByVal Rate As Double, ByVal NPER As Double, ByVal PMTS As Double, Optional ByVal PV As Double = 0, Optional ByVal Type As Byte = 0) As SqlDouble
        Dim FVs As Double

        If Type = 0 Then

            FVs = FV(Rate, NPER, PMTS, PV, DueDate.EndOfPeriod)
        ElseIf Type = 1 Then
            FVs = FV(Rate, NPER, PMTS, PV, DueDate.BegOfPeriod)
        End If

        Return New SqlDouble(FVs)
    End Function
    <Microsoft.SqlServer.Server.SqlFunction(IsDeterministic:=True, IsPrecise:=True)> _
    Public Shared Function fRATE(ByVal NPER As Double, ByVal PMTS As Double, Optional ByVal PV As Double = 0, Optional ByVal FV As Double = 0, Optional ByVal Type As Byte = 0) As SqlDouble
        Dim Rates As Double

        If Type = 0 Then

            Rates = Rate(NPER, PMTS, PV, FV, DueDate.EndOfPeriod, 0.01)
        ElseIf Type = 1 Then
            Rates = Rate(NPER, PMTS, PV, FV, DueDate.BegOfPeriod, 0.01)
        End If

        Return New SqlDouble(Rates)
    End Function

End Class

Excel Rate函数完全在sql中实现

create function uf_Financial_RATE
    (@nper int, @pmt float, @pv float, @fv float, @type bit) 
    returns float
as

begin

    declare @maxIterations int, @i int;
    declare @rate float, @y float, @slope float;
    declare @epsilon float, @guess float;
    declare @pow float, @pow1 float;

    -- Test for rate = 0
    select @y = (@pmt * @nper) + @pv + @fv;
    if (@y <= @epsilon and @y >= -@epsilon)
        return 0;

    -- Use Newton method of approximating the root
    select 
        @maxIterations = 20, 
        @epsilon = 0.00001,
        @guess = 0.1

    select @i = 0, @rate = @guess;

    while @i < @maxIterations
        begin

            select 
                @pow = POWER(1 + @rate, @nper),
                @pow1 = POWER(1 + @rate, @nper - 1);

            -- Find y = f(rate) from excel formula
            select @y =
                @pv * @pow +
                @pmt * (1 + @rate * @type) * ((@pow - 1) / @rate) +
                @fv;

            -- Check if precission is reached
            if @y <= @epsilon and @y >= -@epsilon 
                return @rate;

            -- Find slope value ( y' = f'(rate) ) from the derivative of excel formula
            select @slope =
                @pv * @nper * @pow1 +
                @pmt * ((@type * (@pow - 1) / @rate) + (1 + @rate * @type) * (((@rate * @nper * @pow1) - (@pow - 1)) / POWER(@rate, 2)));

            -- New guess rate
            select @rate = 
                -@y / @slope + @rate;

            -- Next iteration
            select @i = @i + 1;
        end

    -- Could not solve
    return -1;
end

看看这个：更好。在生产系统中使用它之前，首先检查它，使用来自未知源的DLL可能是危险的

CREATE ASSEMBLY [CLRExcel_Financial_Functions]
AUTHORIZATION [dbo]
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WITH PERMISSION_SET = SAFE
GO

CREATE FUNCTION [dbo].[fRATE](@NPER [float], @PMTS [float], @PV [float], @FV [float], @Type [tinyint])
RETURNS [float] WITH EXECUTE AS CALLER
AS 
EXTERNAL NAME [CLRExcel_Financial_Functions].[CLRExcel_Financial_Functions.ExcelFunctions].[fRATE]
GO

CREATE FUNCTION [dbo].[fPV](@Rate [float], @NPER [float], @PMTS [float], @FV [float], @Type [tinyint])
RETURNS [float] WITH EXECUTE AS CALLER
AS 
EXTERNAL NAME [CLRExcel_Financial_Functions].[CLRExcel_Financial_Functions.ExcelFunctions].[fPV]
GO

CREATE FUNCTION [dbo].[fPMT](@Rate [float], @NPer [float], @PV [float], @FV [float], @Type [tinyint])
RETURNS [float] WITH EXECUTE AS CALLER
AS 
EXTERNAL NAME [CLRExcel_Financial_Functions].[CLRExcel_Financial_Functions.ExcelFunctions].[fPMT]
GO

CREATE FUNCTION [dbo].[fNPER](@Rate [float], @PMTS [float], @PV [float], @FV [float], @Type [tinyint])
RETURNS [float] WITH EXECUTE AS CALLER
AS 
EXTERNAL NAME [CLRExcel_Financial_Functions].[CLRExcel_Financial_Functions.ExcelFunctions].[fNPER]
GO

CREATE FUNCTION [dbo].[fFV](@Rate [float], @NPER [float], @PMTS [float], @PV [float], @Type [tinyint])
RETURNS [float] WITH EXECUTE AS CALLER
AS 
EXTERNAL NAME [CLRExcel_Financial_Functions].[CLRExcel_Financial_Functions.ExcelFunctions].[fFV]
GO

create function uf_Financial_RATE
    (@nper int, @pmt float, @pv float, @fv float, @type bit) 
    returns float
as

begin

    declare @maxIterations int, @i int;
    declare @rate float, @y float, @slope float;
    declare @epsilon float, @guess float;
    declare @pow float, @pow1 float;

    -- Test for rate = 0
    select @y = (@pmt * @nper) + @pv + @fv;
    if (@y <= @epsilon and @y >= -@epsilon)
        return 0;

    -- Use Newton method of approximating the root
    select 
        @maxIterations = 20, 
        @epsilon = 0.00001,
        @guess = 0.1

    select @i = 0, @rate = @guess;

    while @i < @maxIterations
        begin

            select 
                @pow = POWER(1 + @rate, @nper),
                @pow1 = POWER(1 + @rate, @nper - 1);

            -- Find y = f(rate) from excel formula
            select @y =
                @pv * @pow +
                @pmt * (1 + @rate * @type) * ((@pow - 1) / @rate) +
                @fv;

            -- Check if precission is reached
            if @y <= @epsilon and @y >= -@epsilon 
                return @rate;

            -- Find slope value ( y' = f'(rate) ) from the derivative of excel formula
            select @slope =
                @pv * @nper * @pow1 +
                @pmt * ((@type * (@pow - 1) / @rate) + (1 + @rate * @type) * (((@rate * @nper * @pow1) - (@pow - 1)) / POWER(@rate, 2)));

            -- New guess rate
            select @rate = 
                -@y / @slope + @rate;

            -- Next iteration
            select @i = @i + 1;
        end

    -- Could not solve
    return -1;
end