If the target field is shared with more than 1 field, the Model::set must detect it and set all fields to the same value. in Join test in https://github.com/atk4/data/blob/45b41461/tests/JoinSqlTest.php#L730
If the target field is shared with more than 1 field, the Model::set must detect it and set all fields to the same value.
in Join test in https://github.com/atk4/data/blob/45b41461/tests/JoinSqlTest.php#L730