Question : problem connecting through sqlplus?

Hi, I have a oracle10g db running on the linux machine. The name of my database is mydb.
I have a schema on the db called 'accounting' with the password 'accounts". Using this username and pw I am able to connect using  isqlplus but when I try and connect using sqlplus i get an errror. My output is as follows;

[oracle@myoracle ~]$ sqlplus /nolog

SQL*Plus: Release 10.2.0.1.0 - Production on Sat Jul 19 13:14:49 2008

Copyright (c) 1982, 2005, Oracle.  All rights reserved.

SQL> conn accounting /accounts
ERROR:
ORA-01034: ORACLE not available
ORA-27101: shared memory realm does not exist
Linux Error: 2: No such file or directory


SQL> conn accounting /accounts@mydb
ERROR:
ORA-12541: TNS:no listener

I am using sqlplus from the same machine the db  is running. What am I doing wrong? Thanks for the help.

A

Answer : problem connecting through sqlplus?

SQL> conn accounting/accounts as sysdba
Connected to an idle instance.

means that your oracle database is not started.

SQL> conn accounting/accounts as sysdba
Connected to an idle instance.
SQL> startup

should try to start the db. if that works without errors, after that, the connection without the as sysdba should work just fine also.