can the date filter be empty to fetch results?

Hello Experts,

We have a simple requirement but looks like complex to achieve.

we have a custom date filed in Master agreement and what our client needs is below report which contains only custom date as optional filter

whenever user gives date and click on show it should give the respective results and also

whenever user makes date filter empty and clicks on show it should fetch all the Master Agreements in which the date field is empty.

Please let me know whether this can be done or not

Thanks

Jitendra