I've had this issue for over a day and looking at the forums, I am wondering if it is due to a Fabrik limitation, though I am rather hoping that it's me missing something obvious. What I am trying to achieve To create an input form to add Joomla users and their groups to enable easy adding of users (later Fabrik CSV import) with some preset values, at this point this just being their allocation to a single user group. Approach taken 1. Created and saved a List linked to ##_users (Joomla users) 2. Linked above list to ##_user_usergroup_map (Joomla user ID and group ID) by using: left JOIN ##_user_usergroup_map ON ##_users.id = ##_user_usergroup_map.user_id 3. Set forms, fields, etc as necessary with the element group_id set to a default of 9 (a new group set up in Joomla) as Integer 10 to match DB setting. Problem The forms add a new user fine, but although they show the default group value of 9, it is only storing the user and group value in ##_user_usergroup_map the first time I use the form. Any subsequent additions of users generate the error. Store row failed: Duplicate entry '0-9' for key 'PRIMARY' SQL=INSERT INTO `##_user_usergroup_map` ( `group_id` ) VALUES ( '9' ) I get the impression that Fabrik needs tables to have unique index (?) but joomla ##_user_usergroup_map doesn't. Not sure if this is the problem or how to get around it. This has stopped me on my tracks. Hopefully I have just missed something obvious as I learn to use Fabrik, any help will be much appreciated.