SELECT 
  COUNT(
    DISTINCT(
      cscart_discussion_posts.post_id
    )
  ) 
FROM 
  cscart_discussion_posts 
  INNER JOIN cscart_discussion ON cscart_discussion.thread_id = cscart_discussion_posts.thread_id 
  INNER JOIN cscart_discussion_messages ON cscart_discussion_messages.post_id = cscart_discussion_posts.post_id 
  INNER JOIN cscart_discussion_rating ON cscart_discussion_rating.post_id = cscart_discussion_posts.post_id 
  LEFT JOIN cscart_products ON cscart_products.product_id = cscart_discussion.object_id 
  LEFT JOIN cscart_products_categories ON cscart_products_categories.product_id = cscart_discussion.object_id 
  LEFT JOIN cscart_categories ON cscart_categories.category_id = cscart_products_categories.category_id 
WHERE 
  1 
  AND cscart_discussion_posts.status = 'A' 
  AND cscart_discussion.object_id IN (18492, 18492) 
  AND cscart_discussion.object_type = 'P' 
  AND cscart_discussion_posts.cp_pr_user_delete = 'N' 
  AND cscart_discussion.type != 'D' 
  AND cscart_discussion.company_id = 1 
  AND cscart_products.status = 'A' 
  AND cscart_categories.status = 'A'