- var_dump: documentation ( source)
- array_udiff: documentation ( source)
<?php
$a1 = [
['target_id' => 124],
['target_id' => 234],
['target_id' => 345],
];
$a2 = [
['target_id' => 123, 'type' => 'node'],
['target_id' => 234, 'type' => 'node'],
['target_id' => 345, 'type' => 'node'],
];
var_dump(array_udiff($a1, $a2, function ($a, $b) {
return ($a['target_id'] == $b['target_id']);
}));