Setting up the DATABASE ENVIRONMENT -

oracle@server123:/data/oracle/data $ . oraenv -- (PRESS ENTER it will ask for the database Name of which environment needs to be set)
.
ORACLE_SID = [rdbms1120] ?

Enter Database Name : ORACLE_DATABASE

and it will set the Environment (the given HOME Location and BIN directory for execution of default scripts / Programmes)




Check Listener running for the database

$: use   " ps -ef|grep tns "

LOCAL AUTHENTICATION DISABLED :

when local authentication is disabled , access can be granted using password file (create password file with password ) and set the environment connect using
sqlplus sys as sysdba
password = (Passwoord which is in the password file )