Ez mit jelent (PHP, MYSQL)?

You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'key = '2'' at line 1

$result_for_act = mysql_query("SELECT * FROM nezzed_regkey WHERE user = '".mysql_real_escape_string($_GET["user_name"])."' AND key = '".mysql_real_escape_string($_GET["key_id"])."'");

$validator_for_act = mysql_num_rows($result);