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 '%midnight%'
	) as profit
group by
	nation,
	o_year
order by
	nation,
	o_year desc;
                                                                                           QUERY PLAN                                                                                            
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 GroupAggregate  (cost=1294005.14..1294010.28 rows=147 width=46) (actual time=110033.164..113654.004 rows=175 loops=1)
   Group Key: nation.n_name, (date_part('year'::text, (orders.o_orderdate)::timestamp without time zone))
   Buffers: shared hit=35901913 read=2242454 dirtied=16291 written=26767
   ->  Sort  (cost=1294005.14..1294005.51 rows=147 width=46) (actual time=110018.673..111437.594 rows=3276721 loops=1)
         Sort Key: nation.n_name, (date_part('year'::text, (orders.o_orderdate)::timestamp without time zone))
         Sort Method: quicksort  Memory: 559093kB
         Buffers: shared hit=35901913 read=2242454 dirtied=16291 written=26767
         ->  Hash Join  (cost=67026.33..1293999.85 rows=147 width=46) (actual time=1050.591..98402.384 rows=3276721 loops=1)
               Hash Cond: (supplier.s_nationkey = nation.n_nationkey)
               Buffers: shared hit=35901905 read=2242454 dirtied=16291 written=26767
               ->  Nested Loop  (cost=67024.77..1293995.53 rows=147 width=24) (actual time=1050.516..95577.625 rows=3276721 loops=1)
                     Buffers: shared hit=35901901 read=2242454 dirtied=16291 written=26767
                     ->  Nested Loop  (cost=67024.33..1293924.28 rows=147 width=24) (actual time=1050.493..51168.858 rows=3276721 loops=1)
                           Buffers: shared hit=23448240 read=1571286 dirtied=16048 written=16790
                           ->  Nested Loop  (cost=67024.04..1293876.85 rows=147 width=28) (actual time=1050.480..39509.582 rows=3276721 loops=1)
                                 Buffers: shared hit=13599542 read=1571286 dirtied=16048 written=16790
                                 ->  Hash Join  (cost=67023.48..352786.19 rows=480472 width=16) (actual time=1050.420..5013.396 rows=436052 loops=1)
                                       Hash Cond: (partsupp.ps_partkey = part.p_partkey)
                                       Buffers: shared hit=144499 read=66981 written=118
                                       ->  Seq Scan on partsupp  (cost=0.00..250958.00 rows=8000000 width=12) (actual time=0.003..2021.763 rows=8000000 loops=1)
                                             Buffers: shared hit=134337 read=36621 written=114
                                       ->  Hash  (cost=65522.00..65522.00 rows=120118 width=4) (actual time=1049.795..1049.795 rows=109013 loops=1)
                                             Buckets: 131072  Batches: 1  Memory Usage: 4857kB
                                             Buffers: shared hit=10162 read=30360 written=4
                                             ->  Seq Scan on part  (cost=0.00..65522.00 rows=120118 width=4) (actual time=0.019..1008.998 rows=109013 loops=1)
                                                   Filter: ((p_name)::text ~~ '%midnight%'::text)
                                                   Rows Removed by Filter: 1890987
                                                   Buffers: shared hit=10162 read=30360 written=4
                                 ->  Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem  (cost=0.56..1.95 rows=1 width=24) (actual time=0.016..0.077 rows=8 loops=436052)
                                       Index Cond: (l_partkey = partsupp.ps_partkey)
                                       Filter: (partsupp.ps_suppkey = l_suppkey)
                                       Rows Removed by Filter: 23
                                       Buffers: shared hit=13455043 read=1504305 dirtied=16048 written=16672
                           ->  Index Scan using pk_supplier on supplier  (cost=0.29..0.31 rows=1 width=8) (actual time=0.003..0.003 rows=1 loops=3276721)
                                 Index Cond: (s_suppkey = lineitem.l_suppkey)
                                 Buffers: shared hit=9848698
                     ->  Index Scan using pk_orders on orders  (cost=0.43..0.47 rows=1 width=8) (actual time=0.012..0.013 rows=1 loops=3276721)
                           Index Cond: (o_orderkey = lineitem.l_orderkey)
                           Buffers: shared hit=12453661 read=671168 dirtied=243 written=9977
               ->  Hash  (cost=1.25..1.25 rows=25 width=30) (actual time=0.023..0.023 rows=25 loops=1)
                     Buckets: 1024  Batches: 1  Memory Usage: 10kB
                     Buffers: shared hit=1
                     ->  Seq Scan on nation  (cost=0.00..1.25 rows=25 width=30) (actual time=0.008..0.012 rows=25 loops=1)
                           Buffers: shared hit=1
 Planning time: 31.417 ms
 Execution time: 113716.815 ms
(46 rows)

COMMIT;
COMMIT