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Q187378: BUG: DoBulkFieldExchange Not Called for MFC Recordset Class

Article: Q187378
Product(s): Microsoft C Compiler
Version(s): WINNT:5.0
Operating System(s): 
Keyword(s): 
Last Modified: 03-MAY-2001

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

- The Microsoft Foundation Classes (MFC), included with:
   - Microsoft Visual C++, 32-bit Enterprise Edition, version 5.0 
   - Microsoft Visual C++, 32-bit Professional Edition, version 5.0 
-------------------------------------------------------------------------------

SYMPTOMS
========

An invalid number of parameters or an assertion can occur when you attempt to
open a CRecordset derived class.

CAUSE
=====

The MFC Recordset class binds parameters to member variables by calling the
DoFieldExchange() member function. When you use bulk row fetching, the binding
is done by calling the DoBulkFieldExchange() member function. However when you
bind parameters, MFC calls a common function, BindParams, to perform the binding
in either case. There is currently a bug with BindParams in that it does not
check to see if bulk row fetching is being used and does not implement
DoBulkFieldExchange() for binding parameters.

RESOLUTION
==========

The best workaround for this problem is to have DoFieldExchange() call
DoBulkFieldExchange() explicitly, as in the following example:

     void CBulkRecordSetSample::DoFieldExchange(CFieldExchange* pFX)
     {
       DoBulkFieldExchange(pFX);
     }

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article. We are researching this bug and will post new
information here in the Microsoft Knowledge Base as it becomes available.

REFERENCES
==========

Visual C++ Programmer's Guide: Adding Program Functionality; Details; Database
Topics (ODBC); Recordset (ODBC); Recordset: Fetching Records in Bulk (ODBC)

Additional query words: kbMFC kbDatabase kbODBC kbVC500bug kbDSupport kbdse

======================================================================
Keywords          :  
Technology        : kbAudDeveloper kbMFC
Version           : WINNT:5.0
Issue type        : kbbug
Solution Type     : kbpending

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

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