FIX: CDatabase::ExecuteSQL() Fails with UNICODE Build

   Invalid SQL statement;
     expected 'DELETE', 'INSERT', 'PROCEDURE', 'SELECT', or 'UPDATE'.
   State:37000,Native:-3500,Origin:
     [Microsoft][ODBC Microsoft Access 7.0 Driver]
					

RESOLUTION

To work around this bug, you have to convert the string yourself, and then cast the resultant ASCII string to an LPCTSTR when you pass it to CDatabase::ExecuteSQL(). The cast is necessary because CDatabase::ExecuteSQL() expects a wide character string.

For example, using the following code to delete all the records in a table will fail in an MFC 4.0 program:

   CString   strSQL = _T("DELETE FROM Table1");
   MyDatabase.ExecuteSQL(strSQL);
				

To make the code work, you need to use code similar to this code:

   #include <winnls.h>  // add this include for WideCharToMultiByte()
   .
   .
   .
   CString   strSQL = _T("DELETE FROM Table1");
   char*     szAscii = new char[strSQL.GetLength() + 1];

   WideCharToMultiByte(CP_ACP,0,strSQL,-1,
     szAscii,strSQL.GetLength() + 1,NULL,NULL);
   MyDatabase.ExecuteSQL((LPCTSTR)szAscii);
   delete [] szAscii;