Auto set the filter to current date, whenever dashboard is opened

[Priyanshu]

Hi folks,
I have created a sql query to see active lives as of any particular date, and that date can be selected by using a filter on the dashboard...however i want it to always take the current date whenever someone opens the dashboard (but not by hardcoding the query with current_date, as i still want the dashboard users to be able to change the date as per their requirement). Any suggestions on how to achieve this?

Thanks

[AndrewMBaines]

Can you make the parameter optional? It's a creation date, so I'm assuming future dates aren't valid.