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 '%red%'
	) as profit
group by
	nation,
	o_year
order by
	nation,
	o_year desc;
                                                                                  QUERY PLAN                                                                                   
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 GroupAggregate  (cost=3478699.34..3478704.03 rows=134 width=46) (actual time=264547.968..268224.160 rows=175 loops=1)
   Buffers: shared hit=30226561 read=800158 dirtied=179 written=4588
   ->  Sort  (cost=3478699.34..3478699.68 rows=134 width=46) (actual time=264533.554..265555.574 rows=3272108 loops=1)
         Sort Key: nation.n_name, (date_part('year'::text, (orders.o_orderdate)::timestamp without time zone))
         Sort Method: quicksort  Memory: 558445kB
         Buffers: shared hit=30226561 read=800158 dirtied=179 written=4588
         ->  Nested Loop  (cost=2810000.76..3478694.61 rows=134 width=46) (actual time=112849.177..241850.259 rows=3272108 loops=1)
               Buffers: shared hit=30226553 read=800158 dirtied=179 written=4588
               ->  Nested Loop  (cost=2810000.76..3478656.39 rows=134 width=24) (actual time=112849.068..221974.567 rows=3272108 loops=1)
                     Buffers: shared hit=23682337 read=800158 dirtied=179 written=4588
                     ->  Nested Loop  (cost=2810000.76..3478395.34 rows=134 width=24) (actual time=112849.031..151871.482 rows=3272108 loops=1)
                           Buffers: shared hit=10840542 read=535757 written=2943
                           ->  Merge Join  (cost=2810000.76..3478356.32 rows=134 width=28) (actual time=112848.971..127668.231 rows=3272108 loops=1)
                                 Merge Cond: ((partsupp.ps_partkey = lineitem.l_partkey) AND (partsupp.ps_suppkey = lineitem.l_suppkey))
                                 Buffers: shared hit=1008502 read=533513 written=2943
                                 ->  Index Scan using pk_partsupp on partsupp  (cost=0.00..603091.33 rows=8000000 width=12) (actual time=0.017..7216.787 rows=7999993 loops=1)
                                       Buffers: shared hit=257826 read=176383 written=1401
                                 ->  Sort  (cost=2810000.76..2818421.73 rows=3368389 width=28) (actual time=112848.626..115952.247 rows=3272108 loops=1)
                                       Sort Key: part.p_partkey, lineitem.l_suppkey
                                       Sort Method: quicksort  Memory: 353938kB
                                       Buffers: shared hit=750676 read=357130 written=1542
                                       ->  Hash Join  (cost=66923.38..2444806.30 rows=3368389 width=28) (actual time=1814.735..107079.766 rows=3272108 loops=1)
                                             Hash Cond: (lineitem.l_partkey = part.p_partkey)
                                             Buffers: shared hit=750673 read=357130 written=1542
                                             ->  Seq Scan on lineitem  (cost=0.00..1668177.78 rows=60090778 width=24) (actual time=0.039..21344.682 rows=59985329 loops=1)
                                                   Buffers: shared hit=732997 read=334281 written=3
                                             ->  Hash  (cost=65522.00..65522.00 rows=112110 width=4) (actual time=1814.366..1814.366 rows=109094 loops=1)
                                                   Buckets: 16384  Batches: 1  Memory Usage: 3836kB
                                                   Buffers: shared hit=17673 read=22849 written=1539
                                                   ->  Seq Scan on part  (cost=0.00..65522.00 rows=112110 width=4) (actual time=0.041..1731.898 rows=109094 loops=1)
                                                         Filter: ((p_name)::text ~~ '%red%'::text)
                                                         Rows Removed by Filter: 1890906
                                                         Buffers: shared hit=17673 read=22849 written=1539
                           ->  Index Scan using pk_supplier on supplier  (cost=0.00..0.28 rows=1 width=8) (actual time=0.006..0.006 rows=1 loops=3272108)
                                 Index Cond: (s_suppkey = lineitem.l_suppkey)
                                 Buffers: shared hit=9832040 read=2244
                     ->  Index Scan using pk_orders on orders  (cost=0.00..1.94 rows=1 width=8) (actual time=0.020..0.020 rows=1 loops=3272108)
                           Index Cond: (o_orderkey = lineitem.l_orderkey)
                           Buffers: shared hit=12841795 read=264401 dirtied=179 written=1645
               ->  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=3272108)
                     Index Cond: (n_nationkey = supplier.s_nationkey)
                     Buffers: shared hit=6544216
 Total runtime: 268367.438 ms
(43 rows)

COMMIT;
COMMIT