PHP &Tree Control

I was looking for the PHP script for dynamical creation of tree control, but I was not succesful, so I made one on my own. The script I'm giving you for review is not quite nice, cause I spent some hours on it and first I thought it is built like:

Node, Item, Item, Node, Item, Item, Item... etc.

I was bid confused when I found it is first getting all nodes, and then all items :D

Ignote \n and \t if you want to, it is just to make the final code readable for debuging :D

Here it is:

<?
include('../Engine/conf.inc.php');
$connection = mysql_pconnect($SQL_Server,$SQL_User,$SQL_PSWD);
mysql_select_db($SQL_DB);


function tree_setup($main_query)
{

    $node_dataset = mysql_query($main_query);	
    $num_nodes = mysql_num_rows($node_dataset);						

    $node_no = 0;
    $item_no = 1;
    
    $result_text = "\t[\t\"\",\n\t\t\t\t";
    $result_value = "\t\t\t{\n\t\t\t\t".$node_no.": [";
    
    while ($row = @mysql_fetch_array($node_dataset)) 
    {
        
        $result_text  .= "\"".$row['ReportGroup']."\"";
        $result_value .= $item_no;
            
        if($node_no+1 < $num_nodes)
        {
            $result_text .= ",";
            $result_value .= ",";
        }
        else
        {
            $result_value .= "],\n";
        }
        $node_no++;
        $item_no++;

        

    }
    
    
    $node_dataset = mysql_query($main_query);	
    $num_nodes = mysql_num_rows($node_dataset);	
    
    $node_no = 1;
    
    while ($row = @mysql_fetch_array($node_dataset)) 
    {
        $node_name = $row['ReportGroup'];
        
        $result_text  .= ",\n\t\t\t\t";
        $result_value .="\t\t\t\t".$node_no.": [";
        
        //echo "Select ReportName From WAIS_Reports WHERE ReportGroup = '".$node_name."' <br><br>";
        $item_dataset = mysql_query("Select ReportName From WAIS_Reports WHERE ReportGroup = '".$node_name."'");							
        
        $num_items = mysql_num_rows($item_dataset);
        $i = 1;
        while ($row = @mysql_fetch_array($item_dataset)) 
        {
            $result_text .= '"'.$row['ReportName'].'"';
            $result_value .= $item_no;
    
            if($i < $num_items)
            {
                $result_text .= ',';
                $result_value .= ',';
                $i++;
            }
            
            $item_no++;
        }
            
        if($node_no < $num_nodes)
        {
            $result_value .= "],\n";
        }
        else
        {
            $result_value .= "]\n";
        }
        $node_no++;

    }
        echo "treeNodeTexts = ".$result_text."\n\t\t\t];\n\n";
        echo "tree = ".$result_value."\t\t\t};\n\n";
}



$SQL_tree_query = "Select DISTINCT ReportGroup From WAIS_Reports";							
tree_setup($SQL_tree_query);

?>

Any comments and improvements are welcome ;-)

PS: I wonder what would happend, if I put other tree control in place of the Item... would it create multilevel tree control or just cause error ? ;-)