Need Help for Array datatype support in crossfilter

I am looking for support for STR Type[] { Array } datatype column support in mapd-crossfilter, is there a possibility to generate Group by (UNNEST) .... Having combination in SQL?

Also If I have to custom change the library to produce Group by (UNNEST) .... Having combination in SQLs is there any possibility to change the code to produce such SQLs?

Apart from this I need to produce Nested SQLs is that supported in crossfilter?