FIX: CLongBinary Causes "Invalid String or Buffer Length"

MORE INFORMATION

1. Copy the implementation of RFX_LongBinary() (Msdev\Mfc\Src\Dbrfx.cpp) into a new .cpp file, and rename the function to something like RFX_LongBinary2(). Create a header file for the .cpp file and include that in your recordset .cpp file. Be sure to #include "stdafx.h" at the top of your new .cpp file and include the .cpp file in your project.
2. Change all RFX_LongBinary() calls in your recordset's DoFieldExchange() to calls to RFX_LongBinary2().
3. In your new RFX_LongBinary2() implementation, copy the following code that appears under "case CFieldExchange::SetFieldNull":

         // Length is signed value, it's limited by LONG_MAX
         if (value.m_dwDataLength >
             (ULONG)(LONG_MAX - labs(SQL_LEN_DATA_AT_EXEC_OFFSET)))
         {
            ASSERT(FALSE);
            *plLength = LONG_MAX - labs(SQL_LEN_DATA_AT_EXEC_OFFSET);
         }
         else
            *plLength = value.m_dwDataLength;
   
         *plLength = SQL_LEN_DATA_AT_EXEC(*plLength);
   							

   Paste this code over the line that contains SQL_DATA_AT_EXEC in the following code, which appears under "case CFieldExchange::Value":

         {
            // Indicate data will be sent after SQLExecute
            *plLength = SQL_DATA_AT_EXEC;       << REPLACE THIS LINE
         }
   						

   This causes the macro to be used instead of the constant.
4. In the CFieldExchange::SetFieldNull case, you can simply comment out the conditional that currently causes the macro to be used only in those cases where m_bUseUpdateSQL is FALSE. Comment out a total of five lines as noted below:

        if (pFX->m_prs->m_bUseUpdateSQL)      // COMMENT OUT THIS LINE
           *plLength = SQL_DATA_AT_EXEC;      // COMMENT OUT THIS LINE
        else                                  // COMMENT OUT THIS LINE
        {                                     // COMMENT OUT THIS LINE
           // Length is signed value, it's limited by LONG_MAX
           if (value.m_dwDataLength >
               (ULONG)(LONG_MAX - labs(SQL_LEN_DATA_AT_EXEC_OFFSET)))
           {
              ASSERT(FALSE);
              *plLength = LONG_MAX - labs(SQL_LEN_DATA_AT_EXEC_OFFSET);
           }
           else
              *plLength = value.m_dwDataLength;
   
           *plLength = SQL_LEN_DATA_AT_EXEC(*plLength);
        }                                     // COMMENT OUT THIS LINE