<?php require_once('../config.php'); $user = mysql_real_escape_string($_GET['username']); mysql_query("DELETE FROM users WHERE username='$user'"); ?>
Je crois que MySQL n'apprécie pas trop les doubles guillemets...
A string is a sequence of bytes or characters, enclosed within either single quote (“'”) or double quote (“"”) characters.
<?php $toto = 'foo'; var_dump($toto); // string(3) "foo" var_dump('$toto'); // string(5) "$toto" var_dump("$toto"); // string(3) "foo"