Some implementation of 'customers who bought this also bought'

gistfile1.php

// Source: http://www.ubercart.org/contrib/2972

<?php
function RiffTrax_uc_cart_view_form($form) {
  drupal_add_css(drupal_get_path('module', 'uc_cart') .'/uc_cart.css');
 

$output = '<div id="cart-form-products">'
          . tapir_get_table('uc_cart_view_table', $form) .'</div>';
  if ((

$page = variable_get('uc_continue_shopping_url', '')) != '<none>') {
    if (variable_get('uc_continue_shopping_type', 'link') == 'link') {
      $continue_shopping_link = l(variable_get('uc_continue_shopping_text', t('Continue shopping')), $page);
    }
    else {
      $continue_shopping_link = drupal_render($form['continue_shopping']);
    }
  }
 

$output .= '<div id="cart-form-buttons"><div id="cart-button-shopping">'
           . $continue_shopping_link .'</div>'
           . drupal_render($form) .'</div>';
          
           $output .= '<div style="padding:8px;" id="cart-related-items">Customers who purchased the items in your shopping cart also bought:<br /> ';
                    
           $cartitems = uc_cart_get_contents();
           $random = mt_rand(0, count($cartitems));
           $random_item = $cartitems[$random];          
            
          

$result = db_query("SELECT that.nid, that.title, COUNT(that.nid) AS frequency 
                        FROM {uc_order_products} AS that 
                        LEFT JOIN {uc_order_products} AS this 
                        USING (order_id)
                        WHERE this.nid = %d AND that.nid != %d
                        GROUP BY that.nid 
                        ORDER BY frequency DESC
                        LIMIT 5", $random_item->nid, $random_item->nid);
            
               while ($upsell = db_fetch_object($result)) {            
        
                   $image = db_result(db_query("SELECT field_image_cache_title FROM {content_field_image_cache} WHERE nid = %d", $upsell->nid));
                   
                   $output .= '<div id="cart-related-item" style="padding:5px; width:18%; float:left; position: relative; text-align:center;"><a href="/'.drupal_get_path_alias("node/".$upsell->nid) .'">
                           <img src="/files/imagecache/thumbnail/files/'.$image.'"><br />
                           '.$upsell->title.'</a><br />';
                        //<a href="cart/add/i'.$upsell->nid.'Up-p'.$upsell->nid.'_q1?destination=cart"><strong>(Add to cart)</strong></a></div>';
               }  
          
           $output .= '</div>';
           
return $output;
}
?>