nolog

/ is a default logon using operating system authentication

/nolog establishes no initial connection to Oracle Database.

When you connect using sysdba or sysoper, then you are sys or public user, no matter what username/password you provide :


C:\>sqlplus /nolog

SQL*Plus: Release 9.2.0.1.0 - Production on Sat Aug 11 06:11:39 2007

Copyright (c) 1982, 2002, Oracle Corporation. All rights reserved.

SQL> show user
USER is ""

SQL> conn / AS SYSDBA
Connected.
SQL> SHOW USER
USER is "SYS"

C:\>sqlplus /nolog

SQL*Plus: Release 9.2.0.1.0 - Production on Sat Aug 11 06:13:02 2007

Copyright (c) 1982, 2002, Oracle Corporation. All rights reserved.

SQL> conn / AS SYSDBA
Connected.
SQL> SHOW USER
USER is "SYS"
SQL> conn / as sysoper
ERROR:
ORA-01031: insufficient privileges

SQL> CONN SCOTT/TIGER AS SYSDBA
Connected.
SQL> SHO USER
USER is "SYS"
SQL> CONN WILLIAM/pass AS SYSOPER
ERROR:
ORA-01031: insufficient privileges


Warning: You are no longer connected to ORACLE.




-------------------------------
Comandos em sequencia para inicio do banco de dados manual

>sqlplus /nolog
>conn / as SYSDBA
>startup


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