Miscellany

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