ORACLE_SID vs. TWO_TASK?

Can somebody please explain the two environment variables ORACLE_SID and TWO_TASK?

I have been under the assumption that when the Oracle server is in the same host as the client (sqlplus under Unix), I have to define the variable ORACLE_SID like this:

setenv ORACLE_SID mydatabase

On the other hand, when the Oracle server is in a remote host, I leave ORACLE_SID undefined, and do this instead:

setenv TWO_TASK mydatabase

So far, this arrangement has worked for me, but after 10g, things are breaking and it seems like I should only use TWO_TASK in either case.

-Ramon Received on Mon Mar 22 2004 - 22:55:01 CST