So to read file on application server?

I have to read file on application server and display the report.

For that i have to use 'Open Dataset' and 'Read Dataset'.

my file on application server having naming convention like

'System ID + Date + TIme of file download'

On selection screen of my report there is only Sytem ID and Date.

I don't have 'Time Stamp' in my report.

So how I can fetch file on Application server.

Please guide me.