Can you explain what's the issue?
For what I can see, you're trying to export a csv file, but the query is empty?
You only need this (use overwrite if you need it):
Then your file is on your path.
After that use a download button on the page with the output data:
What is the dynamic event action code when you click on the export CSV button on the front-end? Even though the table view is filtering the data based on the selected date range, that information also needs to be sent to the CSV export query to apply the same date range filters.
To filter the data in the query, in the dynamic click event, load the CSV export query and pick dynamic values for the $_GET.filter_data_start and $_GET.filter_data_end from the user selected date range values.
