laravel db::query update

$affected = DB::table('users')
              ->where('id', 1)
              ->update(['votes' => 1]);

 DB::table('user')->where('email', $userEmail)->update(array('member_type' => $plan));  

$update = \DB::table('student') ->where('id', $data['id']) ->limit(1) ->update( [ 'name' => $data['name'], 'address' => $data['address'], 'email' => $data['email'], 'contactno' => $data['contactno'] ]);