方法一:修改密码

sqlplus /nolog
conn / as sysdba
alter user user_name identified by new_passwd;

方法二:修改密码生命周期

1.查看密码生命周期
SELECT * FROM dba_profiles WHERE profile='DEFAULT' AND resource_name='PASSWORD_LIFE_TIME';
2.修改密码生命周期为无限制(默认180天)
Alter PROFILE DEFAULT LIMIT PASSWORD_LIFE_TIME UNLIMITED;
3.修改密码
alter user user_name identified by new_passwd;(可使用原来的密码)
注:修改密码后登录,如果报"ORA-28000:用户已被锁"
alter user user_name account unlock;
commit;