html php jquery

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.3/jquery.min.js"></script>
<div id="wrapper">
    <div id="title">Change Character Race</div>
    <form action="getchar.php" method="POST">
            <select id="selectacc" name="selectacc">
                <?php
$conn = new mysqli($host, $dbuser, $dbpass, $authdb);
if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
}

$sql = "SELECT id, username FROM account";

$result = $conn->query($sql);

if ($result->num_rows > 0) {
    while($row = $result->fetch_assoc()) {
        echo "<option value='" . $row["id"]. "'>" . $row['username'] . "</option>";
    }
} else {
    echo "<option value='' disabled>No characters avalible</option>";
}
$conn->close();
?>
            </select>
            <select id="race" name="race" disabled></select>
        </form>
        <script>
        $(function() {
            $('#selectacc').on('change', function() {
                var uid = $(this).val();
                $.post('functions/testscript.php', {id: uid}, function(data) {
                    //Remove all option-tags in #race
                    $('#race').html('');
                    //Make #race selectable
                    $('#race').removeAttr('disabled');
                    //Loop through all items
                    //and adds them to #race
                    $.each(data, function(i) {
                        $('#race')
                            .append($('<option></option>')
                            .attr('value', data[i].id)
                            .text(data[i].name));
                    });
                });
            });
        });
        </script>
</div>