<?php
$u_name = '';
 if (isset($_POST['u_name']))  $u_name = mysql_real_escape_string(strip_tags(trim($_POST['u_name'])));
$u_score = 0;
if (isset($_POST['u_score'])) $u_score = intval(strip_tags(trim($_POST['u_score'])));


$host = "localhost";
$user = "root";
$password = "";
$db = 'my_db';

$con = mysqli_connect($host, $user, $password, $db);
if (mysqli_connect_errno()) {
    printf("Не удалось подключиться: %s\n", mysqli_connect_error());
    exit();
}

try {
    if(!mysqli_query($con, 'insert into `sc` (`name`, `score`) values ("'.$u_name.'", "'.$u_score.'")')){
        printf("Ошибка: %s\n", mysqli_error($con));
    } else {
        echo('ok');
    }
} catch (Exception $e) {
    die('Не удалось');
}

/*
$result = mysqli_query($con, "SELECT * FROM `sc` order by `score` desc limit 10");


if($result)
{
    $rows = mysqli_num_rows($result); // количество полученных строк

    echo "<table border=\"1\"><tr><th></th><th>Имя</th><th>Счет</th></tr>";
    for ($i = 0 ; $i < $rows ; ++$i)
    {
        $row = mysqli_fetch_row($result);
        echo "<tr>";
            for ($j = 0 ; $j < 3 ; ++$j) echo "<td>$row[$j]</td>";
        echo "</tr>";
    }
    echo "</table>";

    // очищаем результат
    mysqli_free_result($result);
}
*/

mysqli_close($con);
?>