Explain for Q8 shows negative selectivity when run against DBT3 scales >= 10. I tried with SF10, and SF30. Output:

EXPLAIN EXTENDED
select o_year, sum(case when nation = 'IRAQ' then volume else 0 end) / sum(volume) as mkt_share
from
(
select
year(o_orderdate) as o_year,
l_extendedprice * (1 - l_discount) as volume,
n2.n_name as nation
from
part,
supplier,
lineitem,
orders,
customer,
nation n1,
nation n2,
region
where
p_partkey = l_partkey
and s_suppkey = l_suppkey
and l_orderkey = o_orderkey
and o_custkey = c_custkey
and c_nationkey = n1.n_nationkey
and n1.n_regionkey = r_regionkey
and r_name = 'MIDDLE EAST'
and s_nationkey = n2.n_nationkey
and o_orderdate between date('1995-01-01') and date ('1996-12-31')
and p_type = 'STANDARD ANODIZED BRASS'
) as all_nations
group by o_year
order by o_year;

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