mysql先排序再分组再排序

Question

原数据：
想要的结果：
y 10-01
y 08-10
y 08-07
r 09-01
r 08-25
r 08-07
ss 08-18
ss 08-07

先对他们按时间排序，再分组，再对组内的数据按时间进行排序

建表语句：
DROP TABLE IF EXISTS testor;
CREATE TABLE testor (
id int(11) NOT NULL,
name varchar(255) DEFAULT NULL,
crdate datetime DEFAULT NULL ON UPDATE CURRENT_TIMESTAMP,
PRIMARY KEY (id)
) ENGINE=MyISAM DEFAULT CHARSET=utf8;

---

-- Records of testor

---

INSERT INTO testor VALUES ('0', 'ss', '2017-08-18 09:07:42');
INSERT INTO testor VALUES ('1', 'y', '2017-08-10 09:07:57');
INSERT INTO testor VALUES ('2', 'r', '2017-08-07 09:08:06');
INSERT INTO testor VALUES ('3', 'r', '2017-08-25 09:08:19');
INSERT INTO testor VALUES ('4', 'r', '2017-09-01 09:08:33');
INSERT INTO testor VALUES ('5', 'ss', '2017-08-07 09:08:53');
INSERT INTO testor VALUES ('6', 'y', '2017-08-07 11:51:12');
INSERT INTO testor VALUES ('7', 'y', '2017-10-01 11:51:23');

Answer 1

select t.name,t.crdate
from testor t
left join(
select * from(
select name, crdate
from testor
order by crdate desc
)q group by q.name
) o on t.name = o.name
order by o.crdate desc,t.name,t.crdate desc;