Untitled

<?php

$servername = "";
$username = "";
$password = "";
$dbname = "";

$conn = new mysqli($servername, $username, $password, $dbname);
if ($conn->connect_error)
{
    die("Connection failed: " . $conn->connect_error);
}

$sql = "SELECT * FROM links
ORDER BY RAND()
LIMIT 1";

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

if ($result->num_rows > 0)
{
    while($row = $result->fetch_assoc())
    {
        $url =  $row['url'];
    }
}
else
{
    echo "0 results";
}
?>

<!DOCTYPE html>
<html lang="en">
    <head>
        <meta charset="utf-8">
        <meta name="viewport" content="width=device-width,initial-scale=1">
        <title>Welcome to my website!!</title>
        <link rel="stylesheet" href="style.css">
        <!--<script src="script.js"></script>-->
        <script>
            function refreshPage(){
                window.location.reload();
            }
        </script>
    </head>
    <body>
        <div class="centered_container">
            <h1>
                <a href="http://<?php echo $url; ?>" target="_blank" onClick="refreshPage()">Welcome to my website!!</a>
            </h1>
        </div>
    </body>
</html>