BEGIN;
BEGIN
EXPLAIN (ANALYZE, BUFFERS)
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=3580826.50..3580829.83 rows=95 width=46) (actual time=208018.198..210936.673 rows=175 loops=1)
   Buffers: shared hit=29982880 read=883819 dirtied=64 written=12463
   ->  Sort  (cost=3580826.50..3580826.74 rows=95 width=46) (actual time=208000.747..208845.452 rows=3253849 loops=1)
         Sort Key: nation.n_name, (date_part('year'::text, (orders.o_orderdate)::timestamp without time zone))
         Sort Method: quicksort  Memory: 555877kB
         Buffers: shared hit=29982880 read=883819 dirtied=64 written=12463
         ->  Nested Loop  (cost=2919823.94..3580823.38 rows=95 width=46) (actual time=111716.241..187782.178 rows=3253849 loops=1)
               Buffers: shared hit=29982872 read=883819 dirtied=64 written=12463
               ->  Nested Loop  (cost=2919823.94..3580796.29 rows=95 width=24) (actual time=111716.126..178412.242 rows=3253849 loops=1)
                     Buffers: shared hit=23475174 read=883819 dirtied=64 written=12463
                     ->  Nested Loop  (cost=2919823.94..3580609.65 rows=95 width=24) (actual time=111715.982..132921.540 rows=3253849 loops=1)
                           Buffers: shared hit=10768738 read=556784 written=5466
                           ->  Merge Join  (cost=2919823.94..3580581.99 rows=95 width=28) (actual time=111715.910..121428.046 rows=3253849 loops=1)
                                 Merge Cond: ((partsupp.ps_partkey = lineitem.l_partkey) AND (partsupp.ps_suppkey = lineitem.l_suppkey))
                                 Buffers: shared hit=990028 read=556507 written=5437
                                 ->  Index Scan using pk_partsupp on partsupp  (cost=0.00..603091.29 rows=8000000 width=12) (actual time=0.009..4435.617 rows=7999997 loops=1)
                                       Buffers: shared hit=280506 read=153703 written=4769
                                 ->  Sort  (cost=2919821.77..2925711.13 rows=2355741 width=28) (actual time=111715.794..113903.617 rows=3253849 loops=1)
                                       Sort Key: part.p_partkey, lineitem.l_suppkey
                                       Sort Method: quicksort  Memory: 352511kB
                                       Buffers: shared hit=709522 read=402804 written=668
                                       ->  Hash Join  (cost=66497.94..2670493.10 rows=2355741 width=28) (actual time=1203.523..108122.841 rows=3253849 loops=1)
                                             Hash Cond: (lineitem.l_partkey = part.p_partkey)
                                             Buffers: shared hit=709519 read=402804 written=668
                                             ->  Seq Scan on lineitem  (cost=0.00..1675253.90 rows=60345590 width=24) (actual time=0.027..14841.101 rows=60045826 loops=1)
                                                   Buffers: shared hit=709514 read=362284 written=3
                                             ->  Hash  (cost=65522.00..65522.00 rows=78075 width=4) (actual time=1203.085..1203.085 rows=108438 loops=1)
                                                   Buckets: 8192  Batches: 1  Memory Usage: 3813kB
                                                   Buffers: shared hit=2 read=40520 written=665
                                                   ->  Seq Scan on part  (cost=0.00..65522.00 rows=78075 width=4) (actual time=0.016..1150.216 rows=108438 loops=1)
                                                         Filter: ((p_name)::text ~~ '%brown%'::text)
                                                         Rows Removed by Filter: 1891562
                                                         Buffers: shared hit=2 read=40520 written=665
                           ->  Index Scan using pk_supplier on supplier  (cost=0.00..0.28 rows=1 width=8) (actual time=0.003..0.003 rows=1 loops=3253849)
                                 Index Cond: (s_suppkey = lineitem.l_suppkey)
                                 Buffers: shared hit=9778710 read=277 written=29
                     ->  Index Scan using pk_orders on orders  (cost=0.00..1.95 rows=1 width=8) (actual time=0.013..0.013 rows=1 loops=3253849)
                           Index Cond: (o_orderkey = lineitem.l_orderkey)
                           Buffers: shared hit=12706436 read=327035 dirtied=64 written=6997
               ->  Index Scan using pk_nation on nation  (cost=0.00..0.27 rows=1 width=30) (actual time=0.001..0.002 rows=1 loops=3253849)
                     Index Cond: (n_nationkey = supplier.s_nationkey)
                     Buffers: shared hit=6507698
 Total runtime: 211042.861 ms
(43 rows)

COMMIT;
COMMIT