Show all records at page load before filtering

I have a page with a list of users. I would like to show all records when the page load but have the possibility to filter this list with buttons.
I create a variable. A button click set the variable value to filter results. This works but when the page load, if the variable have no value, there are no records.
I would like to show all records and then filter. It is possible?

Use the conditional filtering options in the Query Builder, to only apply the filter if your variable has a value:

As always is perfect. Thanks Teodor.