Category subcategory list..code stumper

Question

The following code suppose to output a category sub category list..it only out puts a single row under each category it doesnt do all the subcats...here is the final code i have...i cant figure out why it would only print one row...The sql statement works perfectly in phpadmin..
if(isset($_GET['upload'])&& !isset($_GET['edit_gal'])){
require_once('upload.php');
}elseif(isset($_GET['edit_gal'])){
mysql_select_db($database, $makeconnection);
$query = "SELECT * FROM tbl_gallery g, tbl_subgallery s WHERE s.gal_id=g.gal_id ORDER BY s.gal_id";
$result = mysql_query($query) or die(mysql_error());
$row = mysql_fetch_assoc($result);
$prev_section   = null;
$sectionHeading = false;
//echo '<table border="1" cellpadding="5" cellspacing="2">';
do{
    if($prev_section != $row['gal_name'])
        $prev_section   = $row['gal_name'];
        $sectionHeading = false;
    if(!$sectionHeading)
        echo '<h1>' . $row['gal_name'] . '</h1>';
        $sectionHeading = true;
    else
        echo  $row['subgal_name'].'<p> </p';
}while($row = mysql_fetch_assoc($result));

Answer 1

all I can see from staring at the code you provided is, that the $row['subgal_name'] instance has not been put inside the following paragraph tags -- as it´s now, the paragraphs will be empty
Cheers,
Günter