Определите, какой уровень chlid php

Я пытаюсь получить отношения родительского ребенка и успешно получить это. Но я застрял, как определить, каков уровень ребенка.

Вот мой код

public function getDownline($userid = null) { $category_data = array(); $where = array('parent_id' => $userid); $this->db->where($where); $category_query = $this->db->get('users')->result(); $category_data = array(); foreach ($category_query as $category) { $category_data[$category->id] = array($category); $children = $this->getDownline($category->id); if ($children) { $category_data[$category->id]['children'] = $children; } } return $category_data; } 

Ниже представлена ​​моя структура таблицы

введите описание изображения здесь

Я получаю вывод в этом формате

  [1136] => Array ( [0] => stdClass Object ( [id] => 1136 [gid] => 4 [parent_id] => 1112 [username] => test [email] => abc@abc.com [name] => test [status] => 1 [registerd] => 2017-04-20 08:49:25 [last_login] => 2017-04-21 10:42:25 [password] => 4eca045dfa240f56a1f9d45eaa53b71c6eccd6a7 [tranjection_password] => ) [children] => Array ( [1148] => Array ( [0] => stdClass Object ( [id] => 1148 [gid] => 4 [parent_id] => 1136 [username] => test_downline [email] => kapil@abc.in [name] => test_downline [status] => 1 [registerd] => 2017-04-21 10:42:56 [last_login] => 2017-04-21 11:08:00 [password] => 4eca045dfa240f56a1f9d45eaa53b71c6eccd6a7 [tranjection_password] => ) [children] => Array ( [1150] => Array ( [0] => stdClass Object ( [id] => 1150 [gid] => 4 [parent_id] => 1148 [username] => test1_downline1 [email] => kapil25@abc.in [name] => test1_downline1 [status] => 1 [registerd] => 2017-04-21 11:08:27 [last_login] => 0000-00-00 00:00:00 [password] => 4eca045dfa240f56a1f9d45eaa53b71c6eccd6a7 [tranjection_password] => ) ) ) ) [1149] => Array ( [0] => stdClass Object ( [id] => 1149 [gid] => 4 [parent_id] => 1136 [username] => test_downline2 [email] => kapil1@abc.in [name] => test_downline2 [status] => 1 [registerd] => 2017-04-21 11:06:35 [last_login] => 0000-00-00 00:00:00 [password] => 4eca045dfa240f56a1f9d45eaa53b71c6eccd6a7 [tranjection_password] => ) ) ) )