dump base64 encode data to csv file bug from mysql

I have a table in mysql ,  table like this : 

CREATE TABLE `fakeTable` (
`id` int(11) unsigned NOT NULL AUTO_INCREMENT COMMENT 'ID',
`nick_name` varchar(256) NOT NULL DEFAULT '' COMMENT 'base64 encode Name'
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

nick_name is base64 encode data


When I execute sql like this:
select from_base64(nick_name) as decodeNickName from fakeTable;

I will get decode data from datagrip ,
then I execute dump data from datagrip execute result , 
I find the dump data decodeNickName filed is mojibake, 
the decodeNickName like 0Axxxxxx , 
It's not correct decode data .