groupBy 报错？

$list = DB::table('contacts')
->leftjoin('order_tickets', 'contacts.id', '=', 'order_tickets.contact_id')
->where('order_tickets.order_id', 33)
->groupBy('contacts.id')
->get();

"SQLSTATE[42000]: Syntax error or access violation: 1055 'laravel.contacts.name' isn't in GROUP BY (SQL: select * from contacts left join order_tickets on contacts.id = order_tickets.contact_id where order_tickets.order_id = 33 group by contacts.id)"