>> I expect first to run Server Side Code and than to call URL. Is it possible?
no. It can do either the server side code, or go to the URL.
If you want to do some serveer side code, then redirect it to a new URL, then add a call to p_web.WindowOpen to your server side code.
eg
p_web.Script(p_web.WindowOpen('browseReports'))
cheers
Bruce