PHP:合并和排序两个具有相同值的多维数组

$array1 = array(
    array("id" => 1, "name" => "Alice"),
    array("id" => 2, "name" => "Bob")
);

$array2 = array(
    array("id" => 3, "name" => "Charlie"),
    array("id" => 1, "name" => "David")
);

$mergedArray = array_merge($array1, $array2);

print_r($mergedArray);

Array
(
    [0] => Array
        (
            [id] => 1
            [name] => Alice
        )

    [1] => Array
        (
            [id] => 2
            [name] => Bob
        )

    [2] => Array
        (
            [id] => 3
            [name] => Charlie
        )

    [3] => Array
        (
            [id] => 1
            [name] => David
        )

)

function compareById($a, $b) {
    return $a['id'] - $b['id'];
}

usort($mergedArray, 'compareById');

print_r($mergedArray);

Array
(
    [0] => Array
        (
            [id] => 1
            [name] => Alice
        )

    [1] => Array
        (
            [id] => 1
            [name] => David
        )

    [2] => Array
        (
            [id] => 2
            [name] => Bob
        )

    [3] => Array
        (
            [id] => 3
            [name] => Charlie
        )

)