framework/resources/Functional/aggregates/aggregation/sanity/q10.sql.drill-2190

-- group by column that is not in projection list
-- use distinct with count(distinct ...) 
-- subquery has no correlation

select 	distinct 
	count(distinct a1) 
from 
	t1 
where 
	a1 in 	(	
		select 	distinct 
			count(distinct b2) 
		from 	
			t2 
		group by 
			a2, c2
		) 
group by 
	a1, c1 
order by 
	1;