How to create download button on web template todownload .csv on app server

Hi Experts,

I need to add a button on the web template that will enable the user to download the executed query in .csv format and automatically save it to a designated app server location. the file name must automatically grab the time, date stamp and userid in case there are several users downloading at the same time. I know how to add a button to the web template but dont know how to grab the executed query in .csv formt and save to a designated app server location with the file name requirement above.

Please help!