On RT 3.8.2 and later, RT deployment for Oracle databases is very
straightforward.

You don't need to configure Oracle beforehand. During installation
a user is created and all RT's objects are created in his schema.
The user is created with the following parameters:

    CREATE USER <DatabaseUser> IDENTIFIED BY <DatabasePassword>
        DEFAULT TABLESPACE USERS TEMPORARY TABLESPACE TEMP
        QUOTA UNLIMITED ON USERS

And the user is also granted 'CONNECT' and 'RESOURCE'. It's up to you
to do decide how to manage users, change quotas, table spaces, etc.

RT has an option $DatabaseName which is used to define the SID of
the Oracle database. You don't have to set up the TWO_TASK environment
variable or any helper files for establishing connections.

Example:

    ./configure \
        --with-db-type=Oracle \
        --with-db-database=XE \
        --with-db-host=192.168.0.1 \
        --with-db-dba=system \
        --with-db-rt-user=rtdb1 \
        --with-db-rt-pass=rtdb1secret \
        ... other configure options ...

That should be enough to get you started on Oracle, but to complete
installation you must follow the general instructions in the README file.

As with all databases it is important to analyze the schema and get
current statistics after every significant dataset change.  Oracle's
cost-based optimizer can provide particularly bad performance when the
schema statistics are inaccurate.  To analyze the schema of the user
called RT, execute the following from within sqlplus:

  execute dbms_utility.analyze_schema( 'RT', 'estimate');