CREATE FUNCTION `getNode`(uuid VARCHAR(100)) RETURNS varchar(300) CHARSET utf8
DETERMINISTIC
BEGIN
DECLARE info VARCHAR(200);
DECLARE str VARCHAR(200);
DECLARE real_name VARCHAR(50);
DECLARE is_node TINYINT(1);
DECLARE i INT(10);

WHILE uuid is not null DO
SET info = (select real_name FROM lottery_user WHERE uid = uuid limit 1);
return info;
END WHILE;
RETURN uuid;
END

select getNode("oskjxc25f45sad1f5sdf2sd2f")； 返回的未null
如果是英文字符则会正常