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我有一个关键任务 Access 2003 数据库，它使用 Microsoft SQL Server 数据库迁移助手 (SSMA) 软件从本地 MDB 更改为带有 MS SQL Server 2005 后端的 MDB 前端。

现在，我需要将表链接到的服务器从 IP 地址（即将更改）永久更改为指向同一服务器的主机名。服务器本身没有改变，只是连接字符串。

这是一个无 DSN 连接，因此 ODBC 信息包含在 Access MDB 文件中。如果我尝试在 Access 中刷新表链接，它会提示我输入 DSN（我不想使用它）。

我做了一些谷歌搜索，我发现了几段代码，每次程序启动时都会自动更新。但是，我担心这可能会给用户带来问题或延迟。这是我最好的选择，还是有一些技巧可以永久更改存储在 MDB 中的连接字符串？

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2 回答 2

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您可以使用 VBA 更改链接s的.Connect属性。TableDef

从“立即”窗口查看此示例。（我过去Replace()只是把那条长线分开。）

? Replace(CurrentDb.TableDefs("remote_table").Connect, ";", ";" & vbCrLf)
ODBC;
DRIVER=SQL Server Native Client 10.0;
SERVER=HP64\SQLEXPRESS;
Trusted_Connection=Yes;
APP=Microsoft Office 2003;
WSID=WIN732B;
DATABASE=testbed;

所以我可以用不同的服务器构建一个新字符串，并将新字符串分配给TableDef .Connect属性。

如果这是一项永久性更改，您应该只需要执行一次，而不是每次打开数据库时。

当我完成类似的连接更改时，它一直在不同的服务器之间。所以我删除了 TableDef 并重新创建它，以确保 Access 没有保留任何关于该连接的缓存元信息，这些信息现在已经过时了。但是，在您的情况下，您正在处理相同的物理服务器，只是通过名称而不是 IP 来引用它。我怀疑缓存的信息会让你担心。

于 2012-04-24T17:11:34.287 回答
1

以下代码多年来一直为我服务：

Function LinkTable(DbName As String, SrcTblName As String, _
                   Optional TblName As String = "", _
                   Optional ServerName As String = DEFAULT_SERVER_NAME, _
                   Optional DbFormat As String = "ODBC") As Boolean
Dim db As dao.Database
Dim TName As String, td As TableDef

    On Error GoTo Err_LinkTable

    If Len(TblName) = 0 Then
        TName = SrcTblName
    Else
        TName = TblName
    End If

    'Do not overwrite local tables.'
    If DCount("*", "msysObjects", "Type=1 AND Name=" & Qt(TName)) > 0 Then
        MsgBox "There is already a local table named " & TName
        Exit Function
    End If

    Set db = CurrentDb
    'Drop any linked tables with this name'
    If DCount("*", "msysObjects", "Type In (4,6,8) AND Name=" & Qt(TName)) > 0 Then
        db.TableDefs.Delete TName
    End If

    With db
        Set td = .CreateTableDef(TName)
        td.Connect = BuildConnectString(DbFormat, ServerName, DbName)
        td.SourceTableName = SrcTblName
        .TableDefs.Append td
        .TableDefs.Refresh
        LinkTable = True
    End With

Exit_LinkTable:
    Exit Function
Err_LinkTable:
    'Replace following line with call to error logging function'
    MsgBox Err.Description
    Resume Exit_LinkTable
End Function



Private Function BuildConnectString(DbFormat As String, _
                                    ServerName As String, _
                                    DbName As String, _
                                    Optional SQLServerLogin As String = "", _
                                    Optional SQLServerPassword As String = "") As String
    Select Case DbFormat
    Case "NativeClient10"
        BuildConnectString = "ODBC;" & _
                             "Driver={SQL Server Native Client 10.0};" & _
                             "Server=" & ServerName & ";" & _
                             "Database=" & DbName & ";"
        If Len(SQLServerLogin) > 0 Then
            BuildConnectString = BuildConnectString & _
                                 "Uid=" & SQLServerLogin & ";" & _
                                 "Pwd=" & SQLServerPassword & ";"
        Else
            BuildConnectString = BuildConnectString & _
                                 "Trusted_Connection=Yes;"
        End If

    Case "ADO"
        If Len(ServerName) = 0 Then
            BuildConnectString = "Provider=Microsoft.Jet.OLEDB.4.0;" & _
                                 "Data Source=" & DbName & ";"
        Else
            BuildConnectString = "Provider=sqloledb;" & _
                                 "Server=" & ServerName & ";" & _
                                 "Database=" & DbName & ";"
            If Len(SQLServerLogin) > 0 Then
                BuildConnectString = BuildConnectString & _
                                     "UserID=" & SQLServerLogin & ";" & _
                                     "Password=" & SQLServerPassword & ";"
            Else
                BuildConnectString = BuildConnectString & _
                                     "Integrated Security=SSPI;"
            End If
        End If
    Case "ODBC"
        BuildConnectString = "ODBC;" & _
                             "Driver={SQL Server};" & _
                             "Server=" & ServerName & ";" & _
                             "Database=" & DbName & ";"
        If Len(SQLServerLogin) > 0 Then
            BuildConnectString = BuildConnectString & _
                                 "Uid=" & SQLServerLogin & ";" & _
                                 "Pwd=" & SQLServerPassword & ";"
        Else
            BuildConnectString = BuildConnectString & _
                                 "Trusted_Connection=Yes;"
        End If
    Case "MDB"
        BuildConnectString = ";Database=" & DbName
    End Select
End Function


Function Qt(Text As Variant) As String
Const QtMark As String = """"
    If IsNull(Text) Or IsEmpty(Text) Then
        Qt = "Null"
    Else
        Qt = QtMark & Replace(Text, QtMark, """""") & QtMark
    End If
End Function
于 2012-04-24T17:15:25.163 回答