FIX: Uninitialized String Variables, Empty String Values, Jet Provider, and Errors Occurred

If a WITH statement is used to store an empty string value to one field and an uninitialized string to the very next field, an error will occur when using the Microsoft OLE DB Provider for Jet 3.51 or 4.00 that shipped with MDAC versions prior to 2.5. The error that will occur is as follows on version MDAC versions prior to 2.5: On MDAC 2.5 installations using the OLE DB Provider for Jet 3.51 the following error will occur: No error will occur on MDAC 2.5 using the OLE DB Provider for Jet 4.0 that shipped with it, specifically version 4.0.2927.4.

If it is still necessary to use the OLE DB Provider for Jet 3.51 or MDAC versions prior to 2.5 then it will be necessary to make sure all variables are properly initialized. Otherwise this problem is resolved in the OLE DB Provider for Jet 4.0 that shipped with MDAC 2.5, specifically version 4.0.2927.4.

Microsoft has confirmed that this is a bug in the Microsoft products that are listed at the beginning of this article.

Steps to Reproduce Behavior

NOTE: Change the DBPath variable to point to an .mdb file.

1. Start Visual Basic 6.0.
2. Create a Standard EXE Project.
3. Set the following Project Reference:

   Microsoft ActiveX Data Objects Library
   						

4. Paste the following code into the default form:

   Dim CN As ADODB.Connection
   Dim RS As ADODB.Recordset
   Dim strSQL As String
   Dim DBPath As String
   Dim emptystring As String 'If this is initialized it does not error.
   
   'emptystring = ""
   Set CN = New ADODB.Connection
   Set RS = New ADODB.Recordset
   DBPath = "D:\Program Files\Microsoft Visual Studio\VB98\NWIND.MDB"
       
   On Error Resume Next 'for table drop & creation
   With CN
      .ConnectionString = "Data Source=" & DBPath
      .Provider = "Microsoft.Jet.OLEDB.3.51"
      .Open
      .Execute "drop table testit"
      .Execute "Create table TestIt (Fld1 Text(10), Fld2 Integer, Fld3 Text(10))"
   End With
   On Error GoTo 0 'for table drop & creation
         
   strSQL = "select * from Testit"
   RS.Open strSQL, CN, adOpenKeyset, adLockOptimistic
   RS.AddNew
   
   With RS
       !Fld1 = ""
       !Fld3 = emptystring '"Errors Occurred."
   End With
   					

5. Run the form.