Hi,

To begin, could you just tell me the sql query that returns: avatar and username

SELECT a.avatar,b.username from #__users as b LEFT JOIN #__jsn_users as a ON a.id=b.id WHERE b.id IN ( HERE A QUERY TO RETRIEVE USER IDS OF USERS REGISTERED TO AN EVENT )

I think that this query is not useful for you. Before you should retrieve via Query the IDs of users registered to the event, after you can load JsnUser object to have avatar and username.
- To build the query you need to ask support to dpcalendar support team
- To get users data you can see docs at http://docs.easy-profile.com/index.php/article/jsnuser-object

So

/* here the code to retrieve User IDs from DPcalendar */

require_once(JPATH_SITE.'/components/com_jsn/helpers/helper.php');

foreach( $users_id as $uid ) {

    $user = JsnHelper::getUser( $uid ) ;

    $avatar = $user->avatar ;

    $username = $user->username ;

}

Hi,
Thank you for this quick response
I will think about the 2 choices