Question

概述
我正在使用www.quandl.com免费财务数据来尝试预测资产价格变动

方法
我已经构建了一个使用quandl API下载数据的函数。我正在声明一个位于urlmon.dll system 32文件夹中的Windows API函数。

代码

Option Explicit

#If VBA7 Then
    Private Declare PtrSafe Function URLDownloadToFile Lib "urlmon" Alias "URLDownloadToFileA" ( _
        ByVal pCaller As LongPtr, _
        ByVal szURL As String, _
        ByVal szFileName As String, _
        ByVal dwReserved As LongPtr, _
        ByVal lpfnCB As LongPtr) As LongPtr
#Else
    Private Declare Function URLDownloadToFile Lib "urlmon" Alias "URLDownLoadToFileA" ( _
        ByVal pCaller As Long, _
        ByVal szURL As String, _
        ByVal szFileName As String, _
        ByVal dwReserved As Long, _
        ByVal lpfnCB As LongPtr) As Long
#End If

Sub DownloadSingleFile()

    Dim FileURL As String
    Dim DestinationFile As String

    FileURL = "https://www.quandl.com/api/v3/datasets/WIKI/FB/data.csv?"
    DestinationFile = "C:\Users\hueve\Desktop\TheSystem\Fb.csv"

    URLDownloadToFile 0, FileURL, DestinationFile, 0, 0

End Sub

问题
这个代码有效，它会将数据下载到正确的文件目的地，我想知道是否有办法代替直接下载到文件位置;直接运行到Access数据库表？我知道该函数明确指出它直接下载到文件，但是有一种方法可以直接访问Access DB。此外，我对这些api功能几乎一无所知，所以请放轻松

Answer 1

这是带有一个数据的代码，它可以提取单个数据点（52周的性能）：

    ' save 52 week performance for any scored quarter not saved yet
Set rs = CurrentDb.OpenRecordset("Select * from qryQuarterlyStockDataMissing")
If Not rs.EOF Then
    ' some 52 week performance scores for scored companies are missing.
    rs.MoveLast
    rs.MoveFirst
    intI = rs.RecordCount
    Do While rs.EOF = False
        StatBar_Msg "Updating 52 Week Performance Data for " & intI & " scored periods..."
        strLink = GetQuandl52WeekPerformanceLink(rs![Ticker], rs![Active_Period])
        dbl52WeekPerformance = Nz(GetQuandl52WeekPerformance(strLink), "NULL")
        strSQL = "INSERT INTO tblQuarterlyStockData (SDF_Details_ID, 52WeekPerformance, QuandlLink) " & _
                "VALUES(" & rs![SDF_Details_ID] & "," & CStr(dbl52WeekPerformance) & _
                ",'" & strLink & "')"
        CurrentDb.Execute strSQL
        rs.MoveNext
        intI = intI - 1
    Loop
    rs.Close
    Set rs = Nothing
End If

Public Function GetQuandl52WeekPerformanceLink(strTicker As String, dtDate As Date)
Dim strLink As String
Dim strStartDate As Date
Dim strEndDate As Date
Dim strResponse As String
Dim objHttp As Object
Dim LArray() As String
Dim dtEndDate As Date
Dim dtStartDate As Date

' find nearest weekday date
dtEndDate = GetNearestStockDay(dtDate)
dtStartDate = dtEndDate - 367 ' make it slightly more than a year in case the previous year date falls on a Sunday

GetQuandl52WeekPerformanceLink = "https://www.quandl.com/api/v3/datasets/WIKI/" & strTicker & _
            ".csv?column_index=4&start_date=" & Format(dtStartDate, "yyyy-mm-dd") & _
            "&end_date=" & Format(dtEndDate, "yyyy-mm-dd") & "&collapse=annual&transform=rdiff&api_key=ryCL1ih7fJ1eTH8y9U7E"
End Function



Public Function GetQuandl52WeekPerformance(strLink As String)
Dim strResponse As String
Dim objHttp As Object
Dim LArray() As String

Set objHttp = CreateObject("MSXML2.XMLHTTP")

objHttp.Open "Get", strLink, False
objHttp.send
strResponse = objHttp.responseText
Set objHttp = Nothing

LArray = Split(strResponse, ",")

GetQuandl52WeekPerformance = Null
If LArray(0) = "code" Then
    ' no data returned
Else
    If Len(strResponse) > 12 Then
        GetQuandl52WeekPerformance = LArray(2)
    Else
        ' This stock doesn't have a full year's worth of data
    End If
End If
End Function

Public Function GetNearestStockDay(dtDate As Date) As Date
If Weekday(dtDate) = 1 Then
    GetNearestStockDay = dtDate - 2
ElseIf Weekday(dtDate) = 7 Then
    GetNearestStockDay = dtDate - 1
Else
    GetNearestStockDay = dtDate
End If
End Function

使用urlmon API函数将数据从Quandl.com下载到访问数据库，使用VBA

1 个答案: