Pivot data in date format

Hello!
https://snippet.webix.com/84btp1oz - example of our database and code.

How can i convert or manage the ‘date’ field so the datepicker in the filter would work correctly?

@Sannikovis
you need to define filterMap property
https://docs.webix.com/api__ui.pivot_filtermap_config.html
https://snippet.webix.com/8i9wu5s8