FASTER INSERT ON TABLES IN ORACLE 10g(10.2.0.3)

Sir,

           I want to insert 1500 million rows from a table to another temporary table. For faster insert operations I had done the following:

1) usage of Append clause

2)  Without Indexes insert operations and then creating insert later on

3) Optimising the performance of select query within INsert statement

4) spliting the query and running it across 3 sessions ( instead of giving one month date, I had splitted it  and run across 3 sessions.

5) Running it during offpeak hours.

The server is on SUN Solaris 10 with 24 US IV+ CPU's. with the above, Iam acheiving a rate of around 30 million records per hour.

Is there any mechanism to further improve the performance. Please guide us in this matter and send mail to