How would you visualize data that comes in the millions of records? Developing a application where sometimes when I make a query I get millions or 100 of thousands of records in the results. 

My problem is , when I get these huge result sets, how do I visualize (in charts such as bar, radar, line graphs, etc.) this data? 

Do I just take a sample of the data and visualize that? Do I just go and plot million records? What is the best way to go about this ?
Holoviews visual library can handle very large data http://holoviews.org/ http://holoviews.org/user_guide/Large_Data.html