Online PHP editor | output for P9duh

<?php $array = [ ['task_id' => 1, 'name' => 'do dishes', 'user' => 'bob'], ['task_id' => 1, 'name' => 'do dishes', 'user' => 'liam'], ['task_id' => 2, 'name' => 'vacuum', 'user' => 'liam'], ['task_id' => 3, 'name' => 'Take out thrash', 'user' => 'liam'], ['task_id' => 3, 'name' => 'Take out thrash', 'user' => 'bob'], ]; $result = []; foreach ($array as $row) { extract($row); if (!isset($ref[$task_id])) { $ref[$task_id] = ['task_id' => $task_id, 'name' => $name, 'users' => []]; $result[] =& $ref[$task_id]; } $ref[$task_id]['users'][] = $user; } var_export($result);