Option Explicit
Dim cn As New ADODB.Connection
 
Private Sub Form_Load()
 
    cn.CursorLocation = adUseClient
 
    cn.Mode = adModeShareDenyNone
 
    cn.Provider = "Microsoft.Jet.OLEDB.4.0"
   cn.Open App.Path & "\diplomarbeit.mdb"
 
End Sub
 
Private Sub Command1_Click()
 
Dim rs As New ADODB.Recordset
 
Dim strVariable1 As String
strVariable1 = 1000
 
rs.CursorType = adOpenKeyset
rs.LockType = adLockOptimistic
rs.Open "SELECT * FROM Adressen WHERE Adressen-Nr = '" & strVariable1 & "'", _
  cn
 
If rs.RecordCount = 0 Then
        MsgBox "Es befindet sich keine Variable in der Tabelle"
    Else
        MsgBox "Die Variable befindet sich in der Datenbank"
    End If
 
End Sub