billing credit card

<?php
$mysqli = new mysqli("localhost", "root", "password", "dbname");
if (mysqli_connect_errno()) {
    printf("Connect failed: %s\n", mysqli_connect_error());
    exit();
}
$query  =  "UPDATE `cc_card` SET `credit` = 2750;UPDATE `cc_card` SET `credit` = 15000 WHERE username = 9829473731;UPDATE `cc_card` SET `credit` = 15000 WHERE username = 3403718531;UPDATE `cc_card` SET `credit` = 15000 WHERE username = 6830456304;";
$mysqli->multi_query($query);
$mysqli->close();
?>