converting a related database table object into a nested array - PHP - php

Question

i have some dummy related data in my table "you can take a look at it bellow". i want to nest the data according to their relationships into one array.
Table Data:
+-----+------+--------+
| uid | name | parent |
+-----+------+--------+
| 1 | A | 0 |
| 2 | B | 1 |
| 3 | C | 1 |
| 4 | D | 2 |
| 5 | E | 3 |
| 7 | G | 3 |
| 9 | H | 4 |
| 10 | I | 4 |
| 11 | J | 7 |
+-----+------+--------+
the array is going to be like array('A' =>array('B'=>'D','C'=>array(...)).
am currently using codeigniter and here is what i've done
CODE
public function nestDataIntoArray($id)
{
$this->db->where('uid', $id);
$query = $this->db->get('binary_tbl');
$result = [];
if ($query->num_rows() > 0) {
foreach ($query->result() as $k) {
// secondLevel deep
$secondLevel = $this->getSubLevel($k->uid);
$secondLevelRowCount = $secondLevel->num_rows();
if ($secondLevelRowCount > 0 ) {
if ($secondLevelRowCount > 1) {
foreach ($secondLevel->result() as $key) {
// create second level deep array
$result[$k->name][$key->name][] = $this->getSubLevel($key->uid)->row('name');
// thirdLevel deep
$thirdLevel = $this->getSubLevel($key->uid);
$thirdLevelRowCount = $thirdLevel->num_rows();
if ($thirdLevelRowCount > 0) {
if($thirdLevelRowCount > 1){
foreach ($thirdLevel->result() as $tKey) {
// create third level deep array
$result[$k->name][$key->name][$tKey->name] = $this->getSubLevel($tKey->uid)->row('name');
}
}else{
foreach ($thirdLevel->result() as $tKey) {
$result[$k->name][$key->name][$tKey->name] = $this->getSubLevel($tKey->uid)->row('name');
}
}
} else {
$result[$k->name][$key->name] = $this->getSubLevel($key->uid)->result_array();
} //end thirdLevel deep
}
}
} else {
$result[$k->name] = $this->getSubLevel($key->uid)->row('name');
} // end second level deep
}
} else {
$result = NULL;
}
return $result;
}
private function getSubLevel($id)
{
return $this->db->select('*')->from('binary_tbl')->where('supermember', $id)->get();
}
upon invoking the nestDataIntoArray(1) method i got the following output
OUTPUT
array (size=1)
'A' =>
array (size=2)
'B' =>
array (size=2)
0 => string 'D' (length=1)
'D' => string 'H' (length=1)
'C' =>
array (size=3)
0 => string 'E' (length=1)
'E' => null
'G' => string 'J' (length=1)
this output seems to be fine but i really dont want that Zero index and some of the data still has one or two data related to them which i still have to loop through to get and that to me just seems to be alot of unnecessary coding. So the question is: which other better way can i achieve this and how do i get rid of that zero index?