text: SELECT p.`id`, CONCAT(ct.`name`, ' - ', c.`name`, ' - ', p.`name`) AS 'full_path'
  FROM `problems` AS p
  INNER JOIN `contests` AS c
  ON p.`contest_id` = c.`id`
  INNER JOIN `categories` AS ct
  ON c.`category_id` = ct.`id`
  ORDER BY p.`id`;
  