Data Filter: you have to choose between "conditional" & "grouping"
One can restrict an existing data filter further with the command:df << (Filter Column(:age) << Where(::age == 14));
To add a new data filter group (standard setting: filter1 OR filter2)
one can use:df << Add Filter(Columns(:age), Where(::age == 14));
I just noticed that if the data filter is set to "conditional", it is not possible to add a new filter group.
You can still use the code, but the action...