**First Approch:**

您可以将数据保存为十进制，将最大值保存为：

CREATE TABLE `save_processtime1` (
  `id` INT(11) NOT NULL,
  `point_decimal` DECIMAL(25,20) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=INNODB DEFAULT CHARSET=utf8;

INSERT INTO `save_processtime1` (`id`, `point_decimal`) VALUES('1','0.0034867459008127785');
INSERT INTO `save_processtime1` (`id`, `point_decimal`) VALUES('2','0.0034867459908127785');
INSERT INTO `save_processtime1` (`id`, `point_decimal`) VALUES('3','0.0034867459908127001');
INSERT INTO `save_processtime1` (`id`, `point_decimal`) VALUES('4','0.1000000021200021011');
INSERT INTO `save_processtime1` (`id`, `point_decimal`) VALUES('5','0.0032867459908127785');

mysql>SELECT MAX(point_decimal) FROM save_processtime;
+-----------------------+
| MAX(point_decimal)    |
+-----------------------+
| 0.1000000021200021011 |
+-----------------------+

其他方法：
您可以将此数据保存到字段为varchar的表中。只需获得场的最大值。
虚拟表结构：

CREATE TABLE `save_processtime` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `point_num` varchar(30) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB;

insert into `save_processtime` (`id`, `point_num`) values('1','0.0034867459008127785');
insert into `save_processtime` (`id`, `point_num`) values('2','0.0034867459908127785');
insert into `save_processtime` (`id`, `point_num`) values('3','0.0034867459908127001');
insert into `save_processtime` (`id`, `point_num`) values('4','0.1000000021200021011');
insert into `save_processtime` (`id`, `point_num`) values('5','0.0032867459908127785');

最大时间输出：

mysql> SELECT MAX(point_num) FROM save_processtime;
+-----------------------+
| MAX(point_num)        |
+-----------------------+
| 0.1000000021200021011 |
+-----------------------+

希望这就是你想要的！第一种方法比第二种好：）