check if email exists in MySQL database [duplicate]

Answer 1

if(!filter_var($_POST['email'], FILTER_VALIDATE_EMAIL)) {
    exit('Invalid email address'); // Use your own error handling ;)
}
$select = mysqli_query($connectionID, "SELECT `email` FROM `game` WHERE `email` = '".$_POST['email']."'") or exit(mysqli_error($connectionID));
if(mysqli_num_rows($select)) {
    exit('This email is already being used');
}

Stick that in above the insert query

Answer 2

First, to your question. The most simple is to use the header() function to redirect to a page.

if ( !$email) {
   header('Location: http://example.com/new_page.html' );
} else {
    // Continue with code
}

Secondly, there is a whole lot of issues going on in that code. For example:

• Use PDO
• parameterize your query
• Your control statement should probably look like if(!empty($_POST['name'])) {