php array unset not working as expected - php

Question

I have an array of records I want to create a separate array of skills and want to remove duplicate values, unset not providing desired result somehow, I am not able to find out what's wrong. For example I have record (a) in first skills array at index 0 and I have same record in last skills array at index 1 , I just want to remove any duplicate records but unset removing other records also.
$x = 0;
$y = 0;
$z = 0;
$data = array();
$all_data = array ( 0 => array ( "fname" => "Ann", "skills" => array ( 0 => "a", 1 => "b" )),
1 => array ( "fname" => "Bxx", "skills" => array ( 0 => "c", 1 => "d" )),
2 => array ( "fname" => "Sdd", "skills" => array ( 0 => "e", 1 => "a" ))
);
while( $x < count($all_data)){
while($y < count($all_data[$x]['skills'])){
$data[$x] = $all_data[$x]['skills'];
if (in_array($data[$x][$y], $data[$x])){
unset($data[$x][$y]);
}
$y++;
}
$y = 0;
$x++;
}
The result I am getting is this
Array
(
[0] => Array
(
[0] => a
)
[1] => Array
(
[0] => c
)
[2] => Array
(
[0] => e
[1] => a
)
)
I am expecting
Array
(
[0] => Array
(
[0] => a
[1] => b
)
[1] => Array
(
[0] => c
[1] => d
)
[2] => Array
(
[0] => e
)
)

Answer 1

You could try something like this :
$keys=[];
foreach ($all_data as $index1 => $item) {
if (!isset($item['skills'])) continue;
foreach ($item['skills'] as $index2 => $value) {
if (!in_array($value, $keys)) {
$data[$index1][] = $value ;
$keys[] = $value ;
}
}
}
unset($keys);
print_r($data);
Outputs :
Array
(
[0] => Array
(
[0] => a
[1] => b
)
[1] => Array
(
[0] => c
[1] => d
)
[2] => Array
(
[0] => e
)
)