Categories and Subcategories

[kpowning]

I created the following php code and wondering if there is a better way to make my coding better and for unlimited subcategories?

<?php
$queryrootc = mysql_query("SELECT * FROM categories ORDER BY order_by ASC");
echo "<ul id=\"root\" class=\"menu\">";
$r=100;
while($querymc = mysql_fetch_array($queryrootc)){
	if ($querymc['parentid'] == 0){
		echo "<li><a href=\"javascript:void(0);\" childid=\"c_".$r."\" class=\"cat_close category\">&nbsp;</a>
				  <a href=\"javascript:void(0);\">".$querymc['category']."</a>";
		//Get all results that have the parent id of the root
		$querychksubs = mysql_query("SELECT * FROM categories WHERE parentid = '".$querymc['categoryid']."' ORDER BY order_by ASC");
		$querycntchksubc = mysql_num_rows($querychksubs);
		if ($querycntchksubc){
			echo "<ul id=\"c_".$r."\">";
			$g = 1;
			while($querychksubsresults = mysql_fetch_array($querychksubs)){
				$querysubs2 = mysql_query("SELECT * FROM categories WHERE parentid = '".$querychksubsresults['categoryid']."' ORDER BY order_by ASC");
				$querycntsubs = mysql_num_rows($querysubs2);
				if ($querycntsubs){
					echo "<li><a href=\"javascript:void(0);\" childid=\"c_".$g."\" class=\"cat_close category\">&nbsp;</a>
							<a href=\"javascript:void(0);\">".$querychksubsresults['category']."</a><ul id=\"c_".$g."\">";
					while($getsubs = mysql_fetch_array($querysubs2)){
						echo "<li>".$getsubs['category']."</li>";
					}
					echo "</ul></li>";
				} else {
					echo "<li>".$querychksubsresults['category']."</li>";
				}
			$g++;
			}
			echo "</ul></li>";
		} else {
			echo "</li>";
		}
	} 
$r++;
}
echo "</ul>";
?>

Thanks for looking and any input 🙂