select substr(t.user_code ,7,8)
from table t
where substr(t.user_code ,7,8) < (select to_char(sysdate - interval '60' year,'yyyyMMdd') from dual)
说明：
substr(t.user_code ,7,8) 截取身份证号里面的出生日期
select to_char(sysdate - interval '60' year,'yyyyMMdd') from dual --> 获取当前时间减去60年的时间
substr(t.user_code ,7,8) < (select to_char(sysdate - interval '60' year,'yyyyMMdd') from dual) --> 判断条件