How add a group by option in my custom transformer? Example:
Another example might be if I put a Counter with local scope starting at 0 inside the custom transformer, then I would like to group by for instance _creation_instance - to get three features out all with _count = 0.
In the Custom transformer I see a setting Group by <not set> but I am not able to edit that one (there are no suggestions when opening it). I tried creating a parameter called fme_group_by but that did not work either. How can I do this?
