UPDATE players SET
`player_kill_efficiency` = (
  `player_total_kills` -
  `player_total_teamkills` -
  (`player_deaths_by_world` / 10)
) / (`player_deaths_by_enemy` + 1),

`player_destruction_efficiency` = IFNULL((
  SELECT SUM(`building_efficiency_multiplier`)
  FROM `buildings`
  LEFT JOIN `destructions`
         ON `destruct_building_id` = `building_id`
        AND `destruct_player_id` = %s
  WHERE `destruct_id` IS NOT NULL
) / ((SELECT COUNT(*) FROM `destructions` WHERE `destruct_player_id` = %s) + 1), 0)
WHERE `player_id` = %s