The code

[pirri]

Can anybody explain me this piece of code:

while (!($childval==0))
{
$query="select parentcategoryid from category where categoryid=\"".$childval."\"";
$result=mysql_query($query);
if ($row=mysql_fetch_array($result))
{
$childval= $row["parentcategoryid"];
$query = "select categoryid,name from category where categoryid=\"" . $childval ."\"";
$result=mysql_query($query);
if ($row=mysql_fetch_array($result))
{
$catid[]=$row["categoryid"];
$catname[]=$row["name"];
}
}
}

When I execute this code, never outside of while.

[volleytotal_ch]

the code searches the top entry of a "tree".
I guess you have a table structure like this:

table categry
( categoryid | parentcategoryid | name )

e.g. you have this values in your database:

values
( 1 | 0 | parent )
( 2 | 1 | first_child_to_parent )
( 3 | 1 | second_child_to_parent )
( 4 | 2 | first_child_child_to_first_child )
....

if you start the script with
$childval = 4;

so, the script starts a first time:
- $childval changes to '2'
- $catid[0] is '4'
- $catname[0] is 'first_child_child_to_first_child'

the second time:
- $childval changes to '1'
- $catid[1] is '2'
- $catname[1] is 'first_child_to_parent'

and the third time:
- $childval changes to '0'
- $catid[2] is '1'
- $catname[2] is 'parent'

and then the while loop stops because $childval is '0'.

i guess you have a function to output the values, something like:

rsort($catid);
reset($catid);

while( list($key,$value) = each($catid)) {
  echo $catname[$key]."<br>";
}

if your while loop doesn't end it might be that there is no entry with the value '0' in the field 'parentcategoryid' which belongs to the entry you start with!

hth