On May 23, 2017, we published version 1.25.1 of the table grid editor. This release introduces the multi-level cascading select field.
Now you can create a custom field that can contain many drop-downs. Each drop-down list is built dynamically – using SQL queries. These queries can reference the values of other levels, such that complex cascading effects can be created.
Give it a try – check the marketplace for more information