upgrade na PHP 5.5 - nefunkční mysql

$db = new mysqli('localhost', 'martyn', 'HESLO', 'DB');
if ($db->connect_error) {
	die('Connect Error (' . $db->connect_errno . ') '
		. $db->connect_error);
}

if (!$db->set_charset("utf8")) {
	printf("Error loading character set utf8: %s
", $db->error);
	exit();
} else {
	//printf("Current character set: %s
", $db->character_set_name());
}


function mysql_query($sql) {
	global $db;

	if ($rows=mysqli_query($db, $sql)) {
		// je to cajk
	} else	{
		echo "<div class=error>";
		echo $sql."";
		echo mysqli_error($db);
		echo "</div>";
	}
	/*
	while($row=$rows->fetch_assoc()) {
		echo $row["title"]."<br >";

	};
	*/

	return $rows;

}

function mysql_result($query,$row,$col) {
	global $db;
	$rows=mysqli_fetch_row($query);
	//echo $rows[0];
	return $rows[0];
}

function mysql_num_rows($query) {
	return $query->num_rows;

}

function mysql_fetch_assoc($query) {
	global $db;
	$rows=mysqli_fetch_assoc($query);
	return $rows;
}