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 '%olive%'
	) as profit
group by
	nation,
	o_year
order by
	nation,
	o_year desc;
                                                                                  QUERY PLAN                                                                                   
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 GroupAggregate  (cost=3525716.89..3525721.97 rows=145 width=46) (actual time=253632.554..257069.237 rows=175 loops=1)
   Buffers: shared hit=30228130 read=556798 written=2115
   ->  Sort  (cost=3525716.89..3525717.26 rows=145 width=46) (actual time=253618.424..254630.530 rows=3244659 loops=1)
         Sort Key: nation.n_name, (date_part('year'::text, (orders.o_orderdate)::timestamp without time zone))
         Sort Method: quicksort  Memory: 554585kB
         Buffers: shared hit=30228130 read=556798 written=2115
         ->  Nested Loop  (cost=2855040.92..3525711.69 rows=145 width=46) (actual time=124378.904..231259.386 rows=3244659 loops=1)
               Buffers: shared hit=30228122 read=556798 written=2115
               ->  Nested Loop  (cost=2855040.92..3525670.33 rows=145 width=24) (actual time=124378.841..213582.154 rows=3244659 loops=1)
                     Buffers: shared hit=23738804 read=556798 written=2115
                     ->  Nested Loop  (cost=2855040.92..3525384.99 rows=145 width=24) (actual time=124378.798..157164.347 rows=3244659 loops=1)
                           Buffers: shared hit=10751394 read=547880 written=2110
                           ->  Merge Join  (cost=2855040.92..3525342.76 rows=145 width=28) (actual time=124378.755..137027.621 rows=3244659 loops=1)
                                 Merge Cond: ((partsupp.ps_partkey = lineitem.l_partkey) AND (partsupp.ps_suppkey = lineitem.l_suppkey))
                                 Buffers: shared hit=999706 read=547880 written=2110
                                 ->  Index Scan using pk_partsupp on partsupp  (cost=0.00..603091.33 rows=8000000 width=12) (actual time=0.017..6208.097 rows=7999861 loops=1)
                                       Buffers: shared hit=322698 read=111504 written=2095
                                 ->  Sort  (cost=2855040.91..2864110.61 rows=3627881 width=28) (actual time=124378.625..126675.705 rows=3244659 loops=1)
                                       Sort Key: part.p_partkey, lineitem.l_suppkey
                                       Sort Method: quicksort  Memory: 351793kB
                                       Buffers: shared hit=677008 read=436376 written=15
                                       ->  Hash Join  (cost=67023.48..2459770.66 rows=3627881 width=28) (actual time=1841.439..119463.962 rows=3244659 loops=1)
                                             Hash Cond: (lineitem.l_partkey = part.p_partkey)
                                             Buffers: shared hit=677005 read=436376 written=15
                                             ->  Seq Scan on lineitem  (cost=0.00..1676908.88 rows=60405288 width=24) (actual time=0.034..22780.736 rows=60045310 loops=1)
                                                   Buffers: shared hit=677000 read=395856 written=1
                                             ->  Hash  (cost=65522.00..65522.00 rows=120118 width=4) (actual time=1841.165..1841.165 rows=108018 loops=1)
                                                   Buckets: 16384  Batches: 1  Memory Usage: 3798kB
                                                   Buffers: shared hit=2 read=40520 written=14
                                                   ->  Seq Scan on part  (cost=0.00..65522.00 rows=120118 width=4) (actual time=0.030..1763.441 rows=108018 loops=1)
                                                         Filter: ((p_name)::text ~~ '%olive%'::text)
                                                         Rows Removed by Filter: 1891982
                                                         Buffers: shared hit=2 read=40520 written=14
                           ->  Index Scan using pk_supplier on supplier  (cost=0.00..0.28 rows=1 width=8) (actual time=0.005..0.005 rows=1 loops=3244659)
                                 Index Cond: (s_suppkey = lineitem.l_suppkey)
                                 Buffers: shared hit=9751688
                     ->  Index Scan using pk_orders on orders  (cost=0.00..1.96 rows=1 width=8) (actual time=0.016..0.016 rows=1 loops=3244659)
                           Index Cond: (o_orderkey = lineitem.l_orderkey)
                           Buffers: shared hit=12987410 read=8918 written=5
               ->  Index Scan using pk_nation on nation  (cost=0.00..0.27 rows=1 width=30) (actual time=0.003..0.004 rows=1 loops=3244659)
                     Index Cond: (n_nationkey = supplier.s_nationkey)
                     Buffers: shared hit=6489318
 Total runtime: 257152.984 ms
(43 rows)

COMMIT;
COMMIT