Oracle 10g&11g sys，system 密码忘记设置解决办法

1.启动sqlplus 

2.请输入用户名:  sqlplus/as sysdba 

3.输入口令: 直接回车 

4.连接到: 

   Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production 

   With the Partitioning, OLAP, Data Mining and Real Application Testing options 

   SQL>alter user sys identified by admin; 

  用户已更改。 



  SQL> conn sys/admin as sysdba; 
  已连接。 

  SQL> alter user system identified by manager; 



  用户已更改。  
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1.  安装时选择的自动安装，由于时间久远忘记用户名、密码了，导致现在试了几个默认的用户名密码後（表格中附带默认用户名及密码），都提示无效的用户名、密码，终于在试了下dbsnmp/dbsnmp，提示被锁；
2.用sqlplus/as sysdba登录，提示
3.
SQL> alter user dbsnmp account unlock;

User altered.

SQL> alter user dbsnmp identified by dbsnmp;

User altered.
4.[LongKe@Fedora10 ~]$ sqlplus dbsnmp/dbsnmp;

SQL*Plus: Release 11.1.0.6.0 - Production on Thu Aug 27 02:26:03 2009

Copyright (c) 1982, 2007, Oracle.  All rights reserved.


Connected to:
Oracle Database 11g Enterprise Edition Release 11.1.0.6.0 - Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SQL> show user;
USER is "DBSNMP"


Oracle 10g 默认安装带来的用户名/密码 

Username	Password	Description	See Also
CTXSYS	CTXSYS	The Oracle Text account	Oracle Text Reference
DBSNMP	DBSNMP	The account used by the Management Agent component of Oracle Enterprise Manager to monitor and manage the database	Oracle Enterprise Manager Grid Control Installation and Basic Configuration
LBACSYS	LBACSYS	The Oracle Label Security administrator account	Oracle Label Security Administrator's Guide
MDDATA	MDDATA	The schema used by Oracle Spatial for storing Geocoder and router data	Oracle Spatial User's Guide and Reference
MDSYS	MDSYS	The Oracle Spatial and Oracle interMedia Locator administrator account	Oracle Spatial User's Guide and Reference
DMSYS	DMSYS	The Oracle Data Mining account.	Oracle Data Mining Administrator's Guide Oracle Data Mining Concepts
OLAPSYS	MANAGER	The account used to create OLAP metadata structures. It owns the OLAP Catalog (CWMLite).	Oracle OLAP Application Developer's Guide
ORDPLUGINS	ORDPLUGINS	The Oracle interMedia user. Plug-ins supplied by Oracle and third party format plug-ins are installed in this schema.	Oracle interMedia User's Guide
ORDSYS	ORDSYS	The Oracle interMedia administrator account	Oracle interMedia User's Guide
OUTLN	OUTLN	The account that supports plan stability. Plan stability enables you to maintain the same execution plans for the same SQL statements. OUTLN acts as a role to centrally manage metadata associated with stored outlines.	Oracle Database Performance Tuning Guide
SI_INFORMTN_SCHEMA	SI_INFORMTN_SCHEMA	The account that stores the information views for the SQL/MM Still Image Standard	Oracle interMedia User's Guide
SYS	CHANGE_ON_INSTALL	The account used to perform database administration tasks	Oracle Database Administrator's Guide
SYSMAN	CHANGE_ON_INSTALL	The account used to perform Oracle Enterprise Manager database administration tasks. Note that SYS and SYSTEM can also perform these tasks.	Oracle Enterprise Manager Grid Control Installation and Basic Configuration
SYSTEM	MANAGER	Another account used to perform database administration tasks.	Oracle Database Administrator's Guide

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sqlplus /nolog

conn /as sysdba
alter user system identified by 密码