INSERT INTO Statement not working PHP/MySQLI - php

Question

I've combed through this site non-stop looking for the solution to my problems but have come up empty handed still.
Here's the problem, whenever I use the following INSERT INTO statement nothing is inserted into my database, the code runs without a hitch but at the end of the day my database is still empty(excluding values I manually inserted myself).
I would also like to point out that I ran a SELECT FROM statement that returned manually inserted values from the database nicely.
Anyway here's the code:
Connecting to database
$link = mysqli_connect("localhost", "root", "", "prototype");
Insert code
if ($error) echo "There were error(s) in your signup details:".$error;
else
{
$query = "SELECT * FROM `users` WHERE email = '".mysqli_real_escape_string($link, $_POST['email'])."'";
$result = mysqli_query($link, $query);
$results = mysqli_num_rows($result);
echo $results;
if ($results) echo " This email address is already taken. Would you like to log in?";
else
{
$query = "INSERT INTO `users`(`email`, `password`) VALUES ('".mysqli_real_escape_string($link, $_POST['email']).', '.md5(md5($_POST['email']).$_POST['password'])."')";
mysqli_query($link, $query);
echo "You've been registered!";
$_SESSION['id'] = mysqli_insert_id($link);
print_r($_SESSION);
// Redirect to logged in page
}

Answer 1

Try to change your insert query as below
$query = "INSERT INTO `users`(`email`, `password`) VALUES ('".mysqli_real_escape_string($link, $_POST['email'])."', '".md5(md5($_POST['email']).$_POST['password'])."')";