Thanks for all your comments.

I know this method of updating a record is not the proper way. Since
we can just use the "Update sql statement". But as Paul said. This is
a speed test. I just did it out of my curiosity.

I will be doing the test again and made some changes like you have
suggested and see what will be the results. By the way Daniel, I
perform this test with the database on the same machine.

Helen, do you have any suggestion on this one to improve the IBO
performance?