Oracle 重啓數據庫以及忘記管理員帳戶怎麼辦？

http://docs.oracle.com/cd/B19306_01/server.102/b15658/strt_stp.htm#UNXAR165

http://www.dba-oracle.com/t_oracle_shutdown_immediate_abort.htm

Oracle has three shutdown modes:

·       Normal (default) - waits for in-flight work to complete.  This could take houes.

·       Immediate - terminates all sessions and does a rollback on all 
uncommitted transactions.  

·       Abort - aborts all sessions, leaving current DML in need of rollback, de-allocates the SGA and terminates the background processes. Note that a shutdown abort is NOT evil or dangerous.  The "abort" simply means that Oracle will terminate all active work, which is what most people want during a shutdown!

The "normal" and "immediate" modes can take a long time in you have in-flight transactions, and many Oracle DBA's ensure a swift clean shutdown this way, aborting the sessions, re-starting to allow warmstart rollback of the aborted transactions, and a shutdown immediate to close cleanly:

1. Depending on your default shell, run the oraenv or coraenv script to set the environment variables for the instance that you want to shut down:

   • Bourne, Bash, or Korn shell:

     $ . /usr/local/bin/oraenv

   • C shell:

     % source /usr/local/bin/coraenv

   When prompted, specify the SID for the instance.

2. Run the following commands to shut down the instance:

   $ sqlplus /nolog
   SQL> CONNECT SYS/sys_password as SYSDBA
   SQL> SHUTDOWN NORMAL

   After the instance shuts down, you can quit SQL*Plus.

Restarting an Oracle Database or Automatic Storage ManagementInstance

Caution:

If the database instance uses Automatic Storage Management for storage management, then you must start the Automatic Storage Management instance before you start the database instance.

To restart an Oracle Database or Automatic Storage Management instance:

1. If required, repeat Steps 1 and 2 of the preceding procedure to set the ORACLE_SID and ORACLE_HOMEenvironment variables to identify the SID and Oracle home directory for the instance that you want to start.

2. Run the following commands to start the instance:

   $ sqlplus /nolog
   SQL> CONNECT SYS/sys_password as SYSDBA
   SQL> STARTUP

   After the instance starts, you can exit from SQL*Plus.

忘記Oracle管理員帳戶怎麼辦

參考http://stackoverflow.com/questions/740119/default-passwords-of-oracle-11g

Login into the machine as oracle login user id( where oracle is installed)..

1. Add ORACLE_HOME = <Oracle installation Directory> in Environment variable

2. Open a command prompt

3. Change the directory to %ORACLE_HOME%\bin

4. type the command sqlplus /nolog

5. SQL> connect /as sysdba

6. SQL> alter user SYS identified by "newpassword";

One more check, while oracle installation and database confiuration assistant setup, if you configure any database then you might have given password and checked the same password for all other accounts.. If so, then you try with the password which you have given in your database configuration assistant setup.

Hope this will work for you..