oracle忘記用戶名密碼怎樣辦？？？

1、忘記除SYS、SYSTEM用戶以外的用戶的登陸密碼。

　　用SYS (或SYSTEM)用戶登陸。

　　CONN SYS/PASS_WORD AS SYSDBA;

　　使用以下語句修改用戶的密碼。

　　ALTER USER user_name IDENTIFIED BY newpass;

　　注意：密碼不能全是數字。而且不能是數字開頭。不然會出現：ORA-00988: 口令缺失或無效

　　2、忘記SYS用戶，或者是SYSTEM用戶的密碼。

　　若是是忘記SYSTEM用戶的密碼，能夠用SYS用戶登陸。而後用ALTER USER 密令

　　修改密碼。

　　CONN SYS//PASS_WORD AS SYSDBA;

　　ALTER USER SYSTEM IDENTIFIED BY newpass;

　　若是是忘記SYS用戶的密碼，能夠用SYSTEM用戶登陸。而後用ALTER USER 密令

　　修改密碼。

　　CONN SYSTEM//PASS_WORD ;

　　ALTER USER SYSTEM IDENTIFIED BY newpass;

　3、若是SYS,SYSTEM用戶的密碼都忘記或是丟失。

　　這一項尤爲重要。

方法1、

　　能夠使用ORAPWD.EXE 工具修改密碼。

　　開始菜單->運行->輸入‘CMD’,打開命令提示符窗口，輸入以下命令：

　　orapwd file=D:\oracle\product\10.2.0\db_1\database\pwdctcsys.ora

　　password=newpass

　　這個命令從新生成了數據庫的密碼文件。密碼文件的位置在ORACLE_HOME目錄下

　　的\database目錄下。　　這個密碼是修改sys用戶的密碼。除sys和system其餘用戶的密碼不會改變。

方法2、

1.若是不記得sys用戶的密碼了，採用以下方法能夠修改密碼：
(1)打開cmd，輸入sqlplus /nolog，回車。
(2)輸入「conn / as sysdba」;
(3)輸入「alter user sys identified by 新密碼;」（新密碼必須以字母開頭，另外每條SQL語句後得分號不能忘）
其餘用戶方式同理

2.(1)在cmd中啓動sqlplus；

(2)用sqlplus/as sysdba登陸，使其鏈接到:

OracleDatabase 10g Express Edition Release 10.2.0.1.0 - Production

(3)執行ALTER USER DBSNMP ACCOUNT UNLOCK；

(4) 重新用SQL/PLUS登陸，設置用戶名、密碼；

附：Oracle10g 默認安裝帶來的用戶名/密碼

Username	Password	Description	See Also
CTXSYS	CTXSYS	The OracleText account	OracleText Reference
DBSNMP	DBSNMP	The account used by the Management Agent component of OracleEnterprise Manager to monitor and manage the database	OracleEnterprise Manager Grid Control Installation and Basic Configuration
LBACSYS	LBACSYS	The OracleLabel Security administrator account	OracleLabel Security Administrator's Guide
MDDATA	MDDATA	The schema used by OracleSpatial for storing Geocoder and router data	OracleSpatial User's Guide and Reference
MDSYS	MDSYS	The OracleSpatial and OracleinterMedia Locator administrator account	OracleSpatial User's Guide and Reference
DMSYS	DMSYS	The OracleData Mining account.	OracleData Mining Administrator's Guide OracleData Mining Concepts
OLAPSYS	MANAGER	The account used to create OLAP metadata structures. It owns the OLAP Catalog (CWMLite).	OracleOLAP Application Developer's Guide
ORDPLUGINS	ORDPLUGINS	The OracleinterMedia user. Plug-ins supplied by Oracleand third party format plug-ins are installed in this schema.	OracleinterMedia User's Guide
ORDSYS	ORDSYS	The OracleinterMedia administrator account	OracleinterMedia 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.	OracleDatabase Performance Tuning Guide
SI_INFORMTN_SCHEMA	SI_INFORMTN_SCHEMA	The account that stores the information views for the SQL/MM Still Image Standard	OracleinterMedia User's Guide
SYS	CHANGE_ON_INSTALL	The account used to perform database administration tasks	OracleDatabase Administrator's Guide
SYSMAN	CHANGE_ON_INSTALL	The account used to perform OracleEnterprise Manager database administration tasks. Note that SYS and SYSTEM can also perform these tasks.	OracleEnterprise Manager Grid Control Installation and Basic Configuration
SYSTEM	MANAGER	Another account used to perform database administration tasks.