  select d_year, s_nation, p_category, sum(lo_revenue - lo_supplycost) as profit
    from "date", customer, supplier, part, lineorder
   where lo_custkey = c_custkey
     and lo_suppkey = s_suppkey
     and lo_partkey = p_partkey
     and lo_orderdate = d_datekey
     and c_region = 'AMERICA'
     and s_region = 'AMERICA'
     and (d_year = 1997 or d_year = 1998)
     and (p_mfgr = 'MFGR#1' or p_mfgr = 'MFGR#2')
group by d_year, s_nation, p_category
order by d_year, s_nation, p_category
