O/S level authentication in Oracle DBA

SYS> !

[dba12 dbs] $ vi initrajpar.ora

:wq

[dba12 dbs] $ exit

SYS> startup force  à includes shut abort & startup

[just like restart]

{not suggestible command}

SYS> sho parameter OS_authent_prefix

SYS> create usr raj6x71A identified externally;

The user should have os level authentication.

SYS> grant connect, resource to raj6x 71A;

SYS> !

[dba12 ~] $ pwd

Dba12/raj6x71A

[dba12 ~] $ sqlplus

SQL > sho user raj6x 71A

SQL >

To create password file

[db a 12 dbs] $ vi initrajpor.ora

Remote-login_password file= exclusive

:wq

[dba12 dbs] $ orapwd file = orapw $ ORACLE_SID password= diamond

[dba12 dbs] $ cd

[dba12 ~] $ exit

SYS> startup force

SYS> sho parameter remote_login

Value

Exclusive

SYS> select * from v$ pwfile_users

Now SYS can grant SYSDBA privileges to any other user.

SYS> grant sysdba to usr1;

SYS> startup force

SYS> conn user 1/user1 as sysdba

User1> startup force

SQL> sho user user1

SQL>

ROL =s:

SYS> select * from session _ privs;

SYS> create role pay-1;

SYS> grant create tablespsce, create user to pay-1;

SYS> grant pay-1 to suer – 1;

Dba_role_privs

Role_sys_privs

(views related to roles)

1. One segment can only be created in one table space
2. One table space can have multiple segments.

• One segment is made up of one or more extents.

1. One extent is made up of COB.[contiguous oracle blocks]

• One segment can have its multiple extents in the same or different data files provided these data files belongs to the same table space.
• When a segment’s extents are completely filled up, ORACLE offers another extent to support the srowth of the segments on its own. This is known as DSA [dynamic space allocation] which is limited the free space available in the tablespace.