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Q223074: FIX: Update Does Not Time Out if Data Is Locked

Article: Q223074
Product(s): Microsoft Visual Basic for Windows
Version(s): WINDOWS:5.0,6.0
Operating System(s): 
Keyword(s): kbservicepack kbRDO kbRDO200 kbVBp600 kbVS600sp2 kbVS600SP1 kbVS600sp3fix
Last Modified: 11-JAN-2001

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The information in this article applies to:

- Microsoft Visual Basic Professional Edition for Windows, versions 5.0, 6.0 
- Microsoft Visual Basic Enterprise Edition for Windows, versions 5.0, 6.0 
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SYMPTOMS
========

If you're trying to update your rdoResultset on an rdoConnection with a
CursorDriver of rdUseOdbc, the attempt to update the data in your database will
not time out if that data is locked.

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article.

This bug was corrected in Visual Studio 6.0 Service Pack 3. For more information
about Visual Studio service packs, please see the following articles in the
Microsoft Knowledge Base:

Q194022 INFO: Visual Studio 6.0 Service Packs, What, Where, Why

Q194295 HOWTO: Tell That Visual Studio 6.0 Service Packs Are Installed

MORE INFORMATION
================

When you attempt to update data that is locked, most client-server databases,
such as SQL Server and Oracle, keep trying to update that data until the length
of time specified in the QueryTimeout value has expired. With RDO 2.0 prior to
Visual Studio 6.0 Service Pack 3, the QueryTimeout information was not specified
in the attempt to update and the attempt would never time out.

This problem only occurs when using an rdoConnection with a value of rdUseOdbc
for the CursorDriver property. With all other values for the CursorDriver
property, this behavior does not occur.

Steps to Reproduce Behavior
---------------------------

1. Create a new Visual Basic project.

2. Add a reference to RDO 2.0 in your project.

3. Add the following code to your project.

  Private Sub Form_Load()
      Dim cn1 As rdoConnection, cn2 As rdoConnection
      Dim rs1 As rdoResultset
      Dim strConn As String, strSQL As String
      
      strConn = "Driver={SQL Server};Server=MyServer;" & _
                "Database=pubs;UID=MyUID;PWD=MyPWD;"
      strSQL = "SELECT * FROM Authors"
      
      Set cn1 = New rdoConnection
      cn1.CursorDriver = rdUseOdbc
      cn1.Connect = strConn
      cn1.EstablishConnection
          
      Set rs1 = cn1.OpenResultset(strSQL, rdOpenKeyset, rdConcurValues)
      
      Set cn2 = New rdoConnection
      cn2.CursorDriver = rdUseOdbc
      cn2.Connect = strConn
      cn2.EstablishConnection
      cn2.BeginTrans
      strSQL = "UPDATE Authors SET Au_FName = 'Test1' " & _
               "WHERE Au_ID = '" & rs1!Au_ID & "'"
      cn2.Execute strSQL

      rs1.Edit
      rs1!Au_FName = "Test2"
      rs1.Update
      
      cn2.RollbackTrans
      cn2.Close
      Set cn2 = Nothing
      
      rs1.Close
      Set rs1 = Nothing
      cn1.Close
      Set cn1 = Nothing
  End Sub

This code assumes that you are using RDO 2.0 to communicate with SQL Server 6.5
or 7.0. You need to modify the connection string to communicate with your
database. If you're not using SQL Server, you might also need to modify the
query strings.

4. Run the project.

If you're using the version of RDO 2.0 that ships with Visual Studio 6.0 Service
Pack 3, you'll receive an error message stating that the timeout expired. If
you're using an earlier version of RDO 2.0 (6.00.8169 or prior), the attempt to
update your data will not time out.

Additional query words:

======================================================================
Keywords          : kbservicepack kbRDO kbRDO200 kbVBp600 kbVS600sp2 kbVS600SP1 kbVS600sp3fix 
Technology        : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB500Search kbVB600Search kbVBA500 kbVBA600 kbVB500 kbVB600
Version           : WINDOWS:5.0,6.0
Issue type        : kbbug
Solution Type     : kbfix

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