From: Warren Young
Date: March 19 2008 11:58am
Subject: Re: Problem Handling Null Values
List-Archive: http://lists.mysql.com/plusplus/7523
Message-Id: <47E10001.9050504@etr-usa.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit

Dustin Moore wrote:
> On Tue, 2008-03-18 at 01:18 -0600, Warren Young wrote:
>> 1. if (!result.at(0)["Unit_id"].is_null()) ...
> 
> I don't really understand why I can't get the others to work

StoreQueryResult::operator[] returns Row&.  Row::operator[] returns 
const String&.  String has member is_null() today, but until the next 
version of MySQL++, doesn't have operator==(mysqlpp::null_type), the 
type of mysqlpp::null.  Thus, it can't be tested as null in this way.

(at() is the same as operator[]() in StoreQueryResult and Row, so you 
can substitute it in above where you like.)