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 (
    51480, 51479, 51494, 51495, 132, 112, 
    3, 78, 2, 77, 87, 66, 22421, 22424, 22290, 
    50981, 50982, 133, 45, 143, 50983, 51416, 
    51043, 51471, 51413, 51421, 51057, 
    51472, 51529, 51547, 51459, 51470, 
    51500, 51460, 51457, 51464, 51412, 
    51530, 51501, 51051, 51053, 51510, 
    51551, 51486, 51478, 51469, 51531, 
    51047, 51461, 51467, 51044, 51473, 
    51477, 51437, 51475, 51048, 51525, 
    51462, 51463, 51516, 51532, 51540, 
    51545, 51458
  ) 
GROUP BY 
  p.product_id