mysql timestamp fun

gistfile1.sql

CREATE TABLE `mails` (
  `id` bigint(20) NOT NULL auto_increment,
  `email` varchar(250) NOT NULL,
  `type` char(6) NOT NULL,
  `time` int(11) NOT NULL,
  PRIMARY KEY  (`id`),
  UNIQUE KEY `email` (`email`),
  KEY `time` (`time`),
  KEY `type` (`type`)
) ENGINE=MyISAM;

/* old query */
explain SELECT email, type, time FROM mails WHERE DATE(FROM_UNIXTIME(time)) > DATE_SUB(NOW(), INTERVAL 2 DAY);

/* new query */
explain SELECT email, type, time FROM mails WHERE time > UNIX_TIMESTAMP(NOW() - INTERVAL 2 DAY);