I am new to Oracle. I have installed Oracle 11g R2 standard edition (server software, 2GB download from Oracle).

I found that the 'Environment Variable PATH' has not been set. Which of these directory should I use for the PATH value:-
1. Oracle base, 2. Software location or 3. Database file location

Also do I need to create 'TNS_ADMIN' environment variable and 'TNSNAMES.ora' file

Kindly advice. Thank you