The result of that method call is a string that carefully imitates the output of database shells. For example, under MySQL you get something similar to EXPLAIN for: SELECT `users`.* FROM `users` INNER JOIN `posts` ON `posts`.`user_id` = `users`.`id` WHERE `users`.`id` = 1 +----+-------------+-------+-------+---------------+---------+---------+-------+------+-------------+ | id | select_type | tabl