Order products by stock quantity

Hi Everyone,

I’m currently running a WP 3.8.1 install with WP E-Commerce plugin. The powers that be want to be able to sort their products to move out of stock items to the back of the line.

I have the filter in my functions.php, and it updates the existing query with whatever I put in.

add_filter( ‘posts_orderby’, ‘products_orderby’ );

function products_orderby( $orderby )
{
global $wpdb;
$orderby = <ORDER BY _WPSC_STOCK META_VALUE HERE>;
return $orderby;
}

I know this is incorrect, I need to know what I can put into the function to order this by the meta_value. I’ve been looking everywhere, seen every variation, and nothing seems to work.

Thanks!

https://www.ads-software.com/plugins/wp-e-commerce/