DOCUMENT:Q195837  16-NOV-1998  [vbwin]
TITLE   :PRB: Error Returned When Attempting to Modify JET Database
PRODUCT :Microsoft Visual Basic for Windows
PROD/VER:WINDOWS:5.0,6.0
OPER/SYS:WINDOWS
KEYWORDS:kbVBp500 kbVBp600 kbDAO kberrmsg

======================================================================
---------------------------------------------------------------------
The information in this article applies to:

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

SYMPTOMS
========

When attempting to modify a JET database, the following error is returned:

   "Run-time error '3211': The database engine couldn't lock table '<table
   name>' because it's already in use by another person or process.".

CAUSE
=====

Attempting to create a relation that involves a table that is currently
open can cause this error.

RESOLUTION
==========

The best workaround is to close the recordset that contains the table being
used in the relation.

STATUS
======

This behavior is by design.

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

The following example will open a database (use Nwind.MDB), open a table
within that database, and then attempt to create a relation using the open
table.

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

1. Create a Standard EXE project in Visual Basic. Form1 is created by
   default.

2. Under Project/References, add "Microsoft DAO 3.51 Object Library."

3. Add a CommandButton to Form1 and add the following code under the Click
   event:

      Dim Fld as Field
      Dim Tbl as Recordset
      Dim Rel as Relation
      Dim db as Database
   
      Set db = OpenDatabase("nwind.mdb", True)
   
      Set Tbl = db.OpenRecordset("employees", dbOpenTable)
      ' Note that employees table is used below in creating the relation.
      ' Uncommenting the line below allows the code to work properly.
      ' Tbl.Close
   
      Set Rel = db.CreateRelation("myrel")
      Rel.Table = "Employees"
      Rel.ForeignTable = "Orders"
      Set Fld = Rel.CreateField("EmployeeID")
      Fld.ForeignName = "EmployeeId"
      Rel.Fields.Append Fld
   
      ' eError will occur on next line.
      db.Relations.Append Rel

4. Uncomment the line for closing the recordset and note the relation is
   created and added to the database without error.

Additional query words:
======================================================================
Keywords          : kbVBp500 kbVBp600 kbDAO kberrmsg
Version           : WINDOWS:5.0,6.0
Platform          : WINDOWS
Issue type        : kbprb

=============================================================================

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS
PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND.  MICROSOFT DISCLAIMS
ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  IN NO
EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR
ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL,
CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF
MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE
POSSIBILITY OF SUCH DAMAGES.  SOME STATES DO NOT ALLOW THE EXCLUSION
OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES
SO THE FOREGOING LIMITATION MAY NOT APPLY.

Copyright Microsoft Corporation 1998.