$servername = "localhost";
$username = "tu*****b";
$password = "b*****JVr";
$dbname = "tu*****b";

$conn = new PDO("mysql:host=$servername;dbname=$dbname", $username, $password);

$stmt2 = $conn->prepare("INSERT INTO actions (id, link, validation, ip) VALUES (?, ?, ?, ?)");
$stmt2->bind_param("ssis", $action_id, $link_id, $validation, $user_ip);
$stmt2->execute();

$stmt2->close();
$conn->close();