Question

I have looked through the code so many time and rewritten it and still can’t figure out how to fix the error.

There are lines 6-10;

function login_check ($email, $password) {
$email = mysql_real_escape_string ($email);
$login_query = mysql_query("SELECT COUNT(`user_id`) as `count`,`user_id` FROM `users` WHERE `email`='$email' AND `password`='".md5($password)."'");
return (mysql_result($login_query, 0) == 1) ? mysql_result($login_query, 0, 'user_id') : false;

}

Re-written code;

function login_check ($email, $password) {
    $email = mysql_real_escape_string($email);
    $login_query = mysql_query("SELECT COUNT(`user_id`) as `count`, `user_id` FROM `users` WHERE `email`='$email' AND `password`='".md5($password)."'");
    return (mysql_result($login_query, 0) == 1) ? mysql_result($login_query, 0, 'user_id') : false; 
}

Answer 1

You need a GROUP BY clause on your SQL statement.

"SELECT COUNT(`user_id`) as `count`,`user_id` 
    FROM `users` 
    WHERE `email`='$email' 
        AND `password`='".md5($password)."'
    GROUP BY `user_id`"