I have registered a domain name and the site is under construction. have a hosting place now. i want to upload 3-4 test pages now untill i complete the correct site web pages. the actual site will be hosted in a different place in different IP address after about 1 months time. I want find out whether i will loose the traffic history, hit count and the ranking when i switch my hosting place to adifferent IP address after my site is completed.

I don't think so and you should not worry about ALEXA they are not accurate anyway.

Alexa will not show a ranking unless you have decent traffic.

Most of it will be your visits anyway.

You'll have no ranking or anything for ages.

And as the previous poster said, forget about Alexa, no one takes it at all seriously.

And why do you care how many people have come to a site that's under construction. They will not come back.

Sorry, but that's the way it is.

Get the site finished, then when you have something to care about, worry then.