recursive foreach with fetched rows (urgent)

[spstieng]

Hi, I'm having a webpage demo tomorrow, and I'm stuck.

I'm trying to output a recursive menu tree. Fairly simple one.

Parent tree (ws_ProdCat table)
| ID | Category |
1 CPU
2 HDD
3 RAM

Child tre (ws_ProdSubCat table)
|ID | parentID | Sub category |
1 1 Socket 370
2 1 Socket 478
3 1 Socket A
4 2 IDE
5 2 SCSI
6 2 S-ATA
7 3 Socket 370
8 3 Socket 370
9 3 Socket 478

I connect to the DB successfully.

$query = "select ProdCatID, ProdCat from ws_ProdCat";
$mnuParent = mysql_query($query);
$query = "select ParentID, ProdSubCat from ws_ProdSubCat";
$mnuChild = mysql_query($query);
$arrParent = mysql_fetch_array($mnuParent);
$arrChild = mysql_fetch_array($mnuChild);

Pseudocode:

for ($i=0; $i < sizeof($arrParent); $i++)
{
	foreach $arrChild
	where  $arrChild->ParentID == arrParent->ProdCatID
	Do
		Echo $arrChild['ProdSubCat');
}

I've looked at examples in the PHP docs on FOREACH and how some users have suggested recursive methods using foreach. But I didn't get any wiser.

Is there a simple way of doing this?

[OhLordy]

Why can't you do it from within MySQL?

SELECT ProdCatID, ProdCat, ParentID, ProdSubCat from ws_ProdCat, ws_ProdSubCat WHERE ParentID=ProdCatID

to do it your way you would have to run through $arrChild and dump it in an array like this

<?
while($row=mysql_fetch_array($mnuParent))
{
  $arrChild[]=$row;
}
//then run through the parent and compare
while($arrParent = mysql_fetch_array($mnuParent))
{
  for($i=0;$i<count($arrChild);$i++)
  {
    if($arrChild[$i]['ParentID']=$arrParent['ProdCatID'])
    {
      echo($arrChild[$i]['ProdSubCat']);
    }
  }
}
?>

Putting it in the query would be A LOT easier
HTH
Rob