Knowledge Base

BUG: DoBulkFieldExchange Not Called for MFC Recordset Class

Article ID: 187378

Article Last Modified on 11/21/2006

Microsoft Foundation Class Library 4.2, when used with:
- Microsoft Visual C++ 5.0 Enterprise Edition
- Microsoft Visual C++ 5.0 Professional Edition

This article was previously published under Q187378

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: kbbug kbpending KB187378