<pre>
<?php
$db = new sqlite_db(dirname(__FILE__)."/db.sqlite");
// CREATE TABLE auth_tbl 
//    (login VARCHAR(32), passwd CHAR(32))
$res = $db->query("SELECT * FROM auth_tbl");

/* import result into my_class setting the row number 
 * and indicating that the data is from a database */
while (($obj = $res->fetch_object("my_class", array(TRUE)))) {
    var_dump($obj);
}

class my_class
{
    public $from_db, $row_num=0;
    private $passwd, $crypt_key = "value";

    /* constructor sets the row number 
     * and sets a flag indicating
     * that the data originated from the database */
    function __construct($fdb=FALSE)
    {
        static $counter;
        $this->row_num = (int) $counter++;
        $this->from_db = $fdb;
    }

    private function decode_passwd() { }

    private function encode_passwd() { }

    function change_password()
    {
        if (decode_passwd($this->passwd) == $_POST['passwd']) {
            $new_pass = encode_passwd($_POST['passwd']);
            /* update password query */
        }
    }
}
?>
</pre>