SELECT 
  p.product_id, 
  ifnull(
    count(dp.post_id), 
    0
  ) as discussion_amount_posts 
FROM 
  cscart_discussion 
  INNER JOIN cscart_products as p ON (
    cscart_discussion.object_id = p.product_id
  ) 
  INNER JOIN cscart_discussion_posts as dp ON (
    cscart_discussion.thread_id = dp.thread_id 
    AND cscart_discussion.object_type = 'P' 
    AND cscart_discussion.company_id = 1
  ) 
WHERE 
  dp.status = 'A' 
  and p.product_id in (
    127, 51325, 63, 51326, 135, 50984, 51450, 
    51451, 51343, 51342, 51341, 51340, 
    47, 136, 65, 42, 51376, 51377, 51378, 
    51379, 51380, 134
  ) 
GROUP BY 
  p.product_id