START TRANSACTION; auto commit mode: off select supp_nation, cust_nation, l_year, sum(volume) as revenue from ( select n1.n_name as supp_nation, n2.n_name as cust_nation, extract(year from l_shipdate) as l_year, l_extendedprice * (1 - l_discount) as volume from supplier, lineitem, orders, customer, nation n1, nation n2 where s_suppkey = l_suppkey and o_orderkey = l_orderkey and c_custkey = o_custkey and s_nationkey = n1.n_nationkey and c_nationkey = n2.n_nationkey and ( (n1.n_name = 'VIETNAM' and n2.n_name = 'IRAQ') +-------------+-------------+--------+---------+ | supp_nation | cust_nation | l_year | revenue | +=============+=============+========+=========+ +-------------+-------------+--------+---------+ 0 tuples COMMIT; auto commit mode: on