1、使用oracle用户登录，连接数据库
[oracle@wuzj ~]$ sqlplus /nolog
SQL*Plus: Release 10.2.0.1.0 - Production on Thu Feb 26 12:06:29 2009
Copyright (c) 1982, 2005, Oracle. All rights reserved.
SQL> conn /as sysdba
Connected.
//查看用户
SQL> select username,password from dba_users;
USERNAME PASSWORD
------------------------------ ------------------------------
USER1 BBE7786A584F9103
MGMT_VIEW 4F538DF5F344F348
SYS 8A8F025737A9097A
SYSTEM 970BAA5B81930A40
DBSNMP FFF45BB2C0C327EC
SYSMAN 2CA614501F09FCCC
OUTLN 4A3BA55E08595C81
MDSYS 72979A94BAD2AF80
ORDSYS 7EFA02EC7EA6B86F
EXFSYS 66F4EF5650C20355
DMSYS BFBA5A553FD9E28A
USERNAME PASSWORD
------------------------------ ------------------------------
WMSYS 7C9BA362F8314299
CTXSYS 71E687F036AD56E5
ANONYMOUS anonymous
XDB 88D8364765FCE6AF
ORDPLUGINS 88A2B2C183431F00
SI_INFORMTN_SCHEMA 84B8CBCA4D477FA3
OLAPSYS 3FB8EF9DB538647C
SCOTT F894844C34402B67
TSMSYS 3DF26A8B17D0F29F
BI FA1D2B85B70213F3
PM 72E382A52E89575A
USERNAME PASSWORD
------------------------------ ------------------------------
MDDATA DF02A496267DEE66
IX 2BE6F80744E08FEB
SH 9793B3777CD3BD1A
DIP CE4A36B8E06CA59C
OE 9C30855E7E0CB02D
HR 6399F3B38EDF3288
28 rows selected.
//修改用户口令 格式 alter user 用户名 identified by 新密码;
SQL> alter user system identified by manager;
User altered.
//再次查看，对比发现密码已经更换
SQL> select username,password from dba_users;
USERNAME PASSWORD
------------------------------ ------------------------------
USER1 BBE7786A584F9103
MGMT_VIEW 4F538DF5F344F348
SYS 8A8F025737A9097A
SYSTEM D4DF7931AB130E37
DBSNMP FFF45BB2C0C327EC
SYSMAN 2CA614501F09FCCC
OUTLN 4A3BA55E08595C81
MDSYS 72979A94BAD2AF80
ORDSYS 7EFA02EC7EA6B86F
EXFSYS 66F4EF5650C20355
DMSYS BFBA5A553FD9E28A
USERNAME PASSWORD
------------------------------ ------------------------------
WMSYS 7C9BA362F8314299
CTXSYS 71E687F036AD56E5
ANONYMOUS anonymous
XDB 88D8364765FCE6AF
ORDPLUGINS 88A2B2C183431F00
SI_INFORMTN_SCHEMA 84B8CBCA4D477FA3
OLAPSYS 3FB8EF9DB538647C
SCOTT F894844C34402B67
TSMSYS 3DF26A8B17D0F29F
BI FA1D2B85B70213F3
PM 72E382A52E89575A
USERNAME PASSWORD
------------------------------ ------------------------------
MDDATA DF02A496267DEE66
IX 2BE6F80744E08FEB
SH 9793B3777CD3BD1A
DIP CE4A36B8E06CA59C
OE 9C30855E7E0CB02D
HR 6399F3B38EDF3288
28 rows selected.
SQL>
//现在就可以用此密码链接进行操作了
SQL> connect system/manager
已连接。
==========================
另一种修改值的办法
SQL> alter user system identified by values '2D594E86F93B17A1';
用户已更改。
//在试试这个密码
SQL> connect system/oracle
已连接。
//这个密码就不灵了
SQL> connect system/manager
ERROR:
ORA-01017: invalid username/password; logon denied