Putting in adequate error checking is part and parcel of getting the general function working. If your code can't tell if the database actions worked or not, it's broken. At the least, you can't demonstrate that it isn't broken.

You could try setting RaiseError to true, which will make it blow up when a DBI error occurs. That will be better than nothing, especially if you couple that with CGI::FatalsToBrowser (or whatever that bit is that makes the CGI error messages go to the browser instead of the local error log where you might never see them.