Online PHP editor | refs for 8fuI7

<?php $array = [ ['id' => 1, 'number' => 12345, 'date' => '2022-05-09'], ['id' => 2, 'number' => 123456, 'date' => '2022-05-09'], ['id' => 3, 'number' => 123456, 'date' => '2022-05-09'], ['id' => 3, 'number' => 123456, 'date' => '2022-05-09'], ['id' => 4, 'number' => 123457, 'date' => '2022-05-10'], ['id' => 4, 'number' => 123458, 'date' => '2022-05-11'], ['id' => 3, 'number' => 123459, 'date' => '2022-05-12'] ]; $found = []; foreach ($array as $index => ['id' => $id]) { if (isset($found[$id])) { unset($array[$index], $array[$found[$id]]); } else { $found[$id] = $index; } } var_export($array);