I use VC++ and SQL Server CE 4.0. My task is to add a new row in the table setting NULL into one of the fields. I've read MSDN http://msdn.microsoft.com/ru-ru/library/windows/desktop/ms718116(v=vs.85).aspx:
if Value = N, Length = N, Status = Y, "Can be used to set the value of a column or parameter to NULL or to specify that the provider is to use the default value for an input or input/output parameter in a procedure."
Thus in the DBBINDING struct for the corresponding column a dwPart member should be the DBPART_STATUS and the status is DBSTATUS_S_ISNULL. But it doesn't work. If dwPart is DBPART_VALUE | DBPART_STATUS it will be work. I think it's incorrect behavior.
Also, there is discussion this issue: