在访问表 VBA 中搜索值

Posted 2023-04-19

【中文标题】在访问表 VBA 中搜索值

【英文标题】：Searching for a value in Access Table VBA

【发布时间】：2017-01-20 14:36:41

【问题描述】：

我编写了将 excel 文件导入访问表的代码。导入每个文件时，都会记录文件名并将其保存到名为“FilesDownloaded”的单独表中。

我想添加 vba 代码，在导入文件之前它会检查文件名 (myfile) 是否已保存在“FilesDownloaded”表中。这将防止同一个文件被导入两次。

代码：

Function Impo_allExcel()
Dim myfile
Dim mypath
Dim que As Byte
Dim rs As DAO.Recordset


que = MsgBox("This proces will import all excel items with the .xls in the folder C:\MasterCard. Please make sure that only the files you want imported are located in this folder. Do you wish to proceed?", vbYesNo + vbQuestion)
If que = 7 Then
    Exit Function
Else
    'do nothing and proceed with code
End If

DoCmd.SetWarnings (False)

DoCmd.RunSQL "DELETE * FROM tblMaster_Import;"


MsgBox "Please WAIT while we process this request"



mypath = "C:\Master\"
ChDir (mypath)
myfile = Dir(mypath & "*.xls")



Do While myfile <> ""
  If myfile Like "*.xls" Then
     'this will import ALL the excel files
     '(one at a time, but automatically) in this folder.
     ' Make sure that's what you want.
    'DoCmd.TransferSpreadsheet acImport, 8, "tblMasterCard_Import", mypath & myfile
    DoCmd.TransferSpreadsheet acImport, acSpreadsheetTypeExcel8, "tblMaster_Import", mypath & myfile, 1

    Set rs = CurrentDb.OpenRecordset("FilesDownloaded")
    rs.AddNew
    rs.Fields("Filename").Value = myfile
    rs.Update
    rs.Close
    Set rs = Nothing

  End If
  myfile = Dir()
Loop




'append data to tblAll (risk of duplicates at this point)
DoCmd.RunSQL "INSERT INTO tblAll SELECT tblMaster_Import.* FROM tblMaster_Import;"

DoCmd.OpenQuery "qryUpdateDateField", acViewNormal
''this code will apend to an existing table and runs the risk of doubling data.
DoCmd.SetWarnings (True)

MsgBox "Your upload is complete"

End Function

【问题讨论】：

您要导入的文件有ID吗？也许您可以在表上设置一个主键以避免重复？

【参考方案1】：

一种可能的解决方案是进行查询，它会为您提供表FilesDownloaded 中的行的结果，条件是名称与您的文件相同。像这样的：

countString = "SELECT COUNT(*) FROM [FilesDownloaded] WHERE [NAMEOFCOL] = " & myFile

然后运行查询，如果结果大于1，你显然有。

【讨论】：

我输入的代码为：Do While myfile "" countString = "Select Count() From [FilesDownloaded] Where [Filename] = myfile" If myfile Like ". xls" And countString = 0 然后我收到不匹配的错误消息。帮忙？

您应该运行查询并获得结果。看看***.com/questions/23992226/…和msdn.microsoft.com/en-us/library/office/ff194626.aspx