(string) 
  			SELECT COUNT(*) AS total_comments
  			FROM wall_comments AS c WHERE c.wall_id = ? AND c.parent_id = 0 AND c.status = 1

(string) 
  			SELECT COUNT(*) AS total_comments
  			FROM wall_comments AS c WHERE c.wall_id = ? AND c.parent_id = 0 AND c.status = 1

MySQLi query has prepared entries, but no types or variables specified!