Add new client in native

Hello:   I´m trying to add a new client in a native development but the problem show up when i try to add the users role. I have created a nanoflow to save the new data in the database:                First i retrieve all the user roles                Then i have created a new client object but when i want to fill the user role i obtain the next error:   Is there any possibility of set a reference in native mode? Is there any other way of set the user role to a related table?   Thanks.        
1 answers

While you cannot use a reference set (many-to-many association), you should be able to use a reference (many-to-one or one-to-one). To achieve this, you could use a helper entity with two one-to-many associations instead of one many-to-many association.