PRB: Error Returned When Attempting to Modify JET Database

• 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.

Keywords : kberrmsg kbDAO kbVBp500 kbVBp600 kbGrpVBDB
Version : WINDOWS:5.0,6.0
Platform : WINDOWS
Issue type : kbprb