Getting the updated data from the database in the listbox

Hello All,

I am having a question. Currently I am using QWAAS connection to retrieve the data in the excel sheet and produce the list of results in the excel shhet.

However, in the dashboard I am providing a drop down list to select the date and then the bar chart will produce the results.

Now, my question how to provide a button to the user, so he can click on it and the latest dates will be populated in the listbox, as well as, the chart will populate the results based on the selected new date.