How can i check sql , and use something like do case - php

Question

I am listing the categories and when clicking category it has to show if there is subcategory . If there isnt subcategory it includes products and have to list products. I mean if includes product case b, else case a
I can use query a or b, But i dont know how to check if have products so use query a else use query b.
Sql :
Categories : id | parent_id | name
product to category : id | product_id | category_id
query a (category list):
<?php
$query_product = mysql_query("SELECT * FROM categories WHERE status = '1' AND parent_id = '".$row['id']."' ORDER BY sort_order");
while($row_product = mysql_fetch_array($query_product)){
$product_name = $row_product['name'];
}
?>
query b (product list):
$query_product_id = mysql_query("SELECT * FROM product_to_category WHERE category_id = '".$row['id']."'");
while($row_product_id = mysql_fetch_array($query_product_id)){
//sort order yapilacak.
$query_product = mysql_query("SELECT * FROM products WHERE status = '1' AND id = '".$row_product_id['product_id']."' ORDER BY sort_order");
$row_product = mysql_fetch_array($query_product);
$product_name = $row_product['name'];
}
?>

Answer 1

Sorry for not telling my question clearly.I found a solution like this but couldnt integrate. I can check if there are products.
I have to use a variable like $code includes
<div id="container-portfolio" class="portfolio-4">
<?php
$query_product = mysql_query("SELECT * FROM categories WHERE status = '1' AND parent_id = '".$row['id']."' ORDER BY sort_order");
while($row_product = mysql_fetch_array($query_product)){
if($language != 'TR'){
$query_product_lang = mysql_query("SELECT image FROM categories WHERE language = '".$language."' AND language_parent_id = '".$row_product['id']."'");
$row_product_lang = mysql_fetch_array($query_product_lang);
$product_name = $row_product_lang['name'];
} else {
$product_name = $row_product['name'];
}
?>
and $link
<a href="<?php echo get('site_link'); ?>c/<?php echo $row_product['link']; ?>" >
<img src="<?php echo HTTP_RESIM.'categories/'.$row_product['image']; ?>" alt="" /></a>
Then use the if statement like below. If you can help me for editing variables, i could use the others i think. Getting errors converting html to php for echo code.
Regards
<?php $sql = mysql_query("SELECT * FROM product_to_category WHERE category_id = '".$row['id']."'");
$urun = mysql_num_rows($sql);
if($urun > 0) {
$code= "......";
$link= "....";
} else {
$code= "......";
$link= "....";
}
?>