Online PHP editor | output for XjbvS

<?php $array = array ( 0 => array ( 'id' => 1, 'user_id' => 15, 'booked' => '2020-08-01', 'sendin' => '2020-08-03', 'pickup' => '2020-08-08', 'duration' => 5 ), 1 => array ( 'id' => 2, 'user_id' => 15, 'booked' => '2020-08-01', 'sendin' => '2020-08-03', 'pickup' => '2020-08-08', 'duration' => 5 ) ); $user_id = 15; $ids = array_map(function ($a) { return $a['id']; }, array_filter($array, function ($a) use ($user_id) { return $a['user_id'] == $user_id; }) ); print_r($ids); $ids = array_map(function ($k) use ($array) { return $array[$k]['id']; }, array_keys(array_column($array, 'user_id'), $user_id) ); print_r($ids);