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 (
    51165, 51164, 51163, 51162, 51161, 52, 
    51169, 51168, 51167, 51166, 90, 51171, 
    51170, 51176, 51174, 51173, 51172, 
    91, 51182, 51180, 51179, 51178, 51177, 
    93, 51183, 20, 51188, 51187, 51186, 
    51185, 51184, 51194, 51193, 51192, 
    51191, 51190, 51189, 19, 51201, 51200, 
    51199, 51198, 51197, 51196, 51195, 
    131, 51564, 51568, 51569, 51570, 51571, 
    51572, 51573, 51566, 51578, 51579, 
    51580, 51581
  ) 
GROUP BY 
  p.product_id