$constructionEmployees = DB::table('order_construction_employees')
->select('order_construction_employees.id', 'order_construction_employees.order_id', 'order_construction_employees.employee_id');
$employees = DB::table("order_dismantling_employees")
->select('order_dismantling_employees.id', 'order_dismantling_employees.order_id', 'order_dismantling_employees.employee_id')
->union($constructionEmployees)
->where('employee_id', session('employee_id'));
->get();
Надеюсь, что это поможет вам