Infinite Loop Problem

Hi,
In the preperation step if a node do not have inbound links

$Sql = "select pagerank.master, tmp_pr.nroout from pagerank inner join tmp_pr on (tmp_pr.id = pagerank.master) where pagerank.slave = ".$row['id'];

do not return any value.

$formula is updated according to the result of the above query so it is empty.

all the rows in tmp_pr whose formula value is empty are selected in a loop and so this process is never ends

solution is replace:
$formula = "";

by:
$formula = "";
if (mysql_num_rows($xSql) == 0) {
$formula .= "0 + ";
}