BEGIN; BEGIN EXPLAIN select nation, o_year, sum(amount) as sum_profit from ( select n_name as nation, extract(year from o_orderdate) as o_year, l_extendedprice * (1 - l_discount) - ps_supplycost * l_quantity as amount from part, supplier, lineitem, partsupp, orders, nation where s_suppkey = l_suppkey and ps_suppkey = l_suppkey and ps_partkey = l_partkey and p_partkey = l_partkey and o_orderkey = l_orderkey and s_nationkey = n_nationkey and p_name like '%brown%' ) as profit group by nation, o_year order by nation, o_year desc; QUERY PLAN ----------------------------------------------------------------------------------------------------------------------------------------- GroupAggregate (cost=3329570.37..3329574.33 rows=113 width=46) -> Sort (cost=3329570.37..3329570.66 rows=113 width=46) Sort Key: nation.n_name, (date_part('year'::text, (orders.o_orderdate)::timestamp without time zone)) -> Nested Loop (cost=2665002.34..3329566.52 rows=113 width=46) -> Nested Loop (cost=2665002.34..3329534.29 rows=113 width=24) -> Nested Loop (cost=2665002.34..3329314.15 rows=113 width=24) -> Merge Join (cost=2665002.34..3329281.25 rows=113 width=28) Merge Cond: ((partsupp.ps_partkey = lineitem.l_partkey) AND (partsupp.ps_suppkey = lineitem.l_suppkey)) -> Index Scan using pk_partsupp on partsupp (cost=0.00..603091.29 rows=8000000 width=12) -> Sort (cost=2665002.32..2672064.50 rows=2824874 width=28) Sort Key: part.p_partkey, lineitem.l_suppkey -> Hash Join (cost=66698.15..2362320.53 rows=2824874 width=28) Hash Cond: (lineitem.l_partkey = part.p_partkey) -> Seq Scan on lineitem (cost=0.00..1666924.32 rows=60044932 width=24) -> Hash (cost=65522.00..65522.00 rows=94092 width=4) -> Seq Scan on part (cost=0.00..65522.00 rows=94092 width=4) Filter: ((p_name)::text ~~ '%brown%'::text) -> Index Scan using pk_supplier on supplier (cost=0.00..0.28 rows=1 width=8) Index Cond: (s_suppkey = lineitem.l_suppkey) -> Index Scan using pk_orders on orders (cost=0.00..1.94 rows=1 width=8) Index Cond: (o_orderkey = lineitem.l_orderkey) -> Index Scan using pk_nation on nation (cost=0.00..0.27 rows=1 width=30) Index Cond: (n_nationkey = supplier.s_nationkey) (23 rows) COMMIT; COMMIT