Question: I have a website where I gather browser statistics.

I have an SQL table (T_Visits), with the following columns:
uniqueidentifier Visit_UID,
uniqueidentifier User_UID,
datetime Visit_DateTime,
float Screen_w,
float Screen_h,
float Resolution = Screen_w * Screen_h
varchar resolutionstring = screen_w + ' x ' + screen_h


Now I want to get the maximum/minimum resolution each user had:

Select User_UID, max(resolution) from T_Visits GROUP BY User_UID

How can I get the corresponding resolution string ?
I mean I can get the max(screen_w) and max(screen_h), but there's no guarantee that the corresponding resolutionstring would be max(screen_w) +' x '+ max(screen_h)