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 (
    325721, 21545, 18228, 163607, 164330, 
    169528, 175066, 184043, 191208, 216438, 
    263004, 279659, 295751, 307166, 308366, 
    315969, 315971, 317489, 317495, 317523, 
    317945, 321995, 321998, 324572
  ) 
GROUP BY 
  p.product_id