I want to Retrive Downtree of my current Tree - php

Question

I have the below tree with present data. I want tree below 103 only.
+----------------+----------------+
| child | parent |
+----------------+----------------+
| 216 | 103 |
| 217 | 216 |
| 88 | 216 |
| 102 | NULL |
| 103 | 102 |
| 104 | 102 |
+----------------+----------------+
the output should be a below format
102
/ \
103 104
/
216
/ \
217 218
from this
103
/
216
/ \
217 218
I need this in Mysql
I tried to get 103 child, then I get 216. again I tried child of 216. and so on in my MYSQL until end. How I get, the tree End?

Answer 1

Below is the code which you can alter as per the requirement.
The sample code can be used in Laravel as a Helper function to get all the child nodes.
class UserUtility
{
public static function children_ids($id)
{
$children = UserUtility::flat_children($id);
return !empty($children) ? array_column($children, 'id') : array();
}
public static function flat_children($id)
{
$children = UserUtility::get_immediate_children($id, $with_trashed, true, $role_id);
if (!empty($children)) {
foreach ($children as $child) {
$container[] = $child;
$container = UserUtility::flat_children($child['id'], $with_trashed, $container, $role_id);
}
}
return $container;
}
public static function get_immediate_children($id)
{
$children = User::withoutGlobalScopes()->where('parent_id', $id)->get(); // get the children data from DB
$children = $as_array && !is_null($children) ? $children->toArray() : array();
return $children;
}
}