WOW .... Classic ASP is approx 20 yrs ago and Tableau is the last decade BUT I've used both
I think you want to get access to the database, so not really anything to do with ASP at all. You just need the connection string and the proper drivers to make Tableau work (although I wonder if it will work).
Do you know of your database is Access or SQL Server ?
If it's SQL Server do you know what version it is ?