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 '%tomato%'
	) as profit
group by
	nation,
	o_year
order by
	nation,
	o_year desc;
                                                                                   QUERY PLAN                                                                                   
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 GroupAggregate  (cost=3388245.15..3388249.59 rows=127 width=46) (actual time=411659.367..414870.322 rows=175 loops=1)
   Buffers: shared hit=30354846 read=830618 dirtied=79 written=4917
   ->  Sort  (cost=3388245.15..3388245.47 rows=127 width=46) (actual time=411647.102..412529.842 rows=3289434 loops=1)
         Sort Key: nation.n_name, (date_part('year'::text, (orders.o_orderdate)::timestamp without time zone))
         Sort Method: quicksort  Memory: 560881kB
         Buffers: shared hit=30354846 read=830618 dirtied=79 written=4917
         ->  Nested Loop  (cost=2720840.13..3388240.71 rows=127 width=46) (actual time=169081.486..389247.863 rows=3289434 loops=1)
               Buffers: shared hit=30354838 read=830618 dirtied=79 written=4917
               ->  Nested Loop  (cost=2720840.13..3388204.49 rows=127 width=24) (actual time=169081.428..360926.225 rows=3289434 loops=1)
                     Buffers: shared hit=23775970 read=830618 dirtied=79 written=4917
                     ->  Nested Loop  (cost=2720840.13..3387955.40 rows=127 width=24) (actual time=169081.308..235471.998 rows=3289434 loops=1)
                           Buffers: shared hit=10728849 read=702079 written=2710
                           ->  Merge Join  (cost=2720840.13..3387918.42 rows=127 width=28) (actual time=169081.276..187150.511 rows=3289434 loops=1)
                                 Merge Cond: ((partsupp.ps_partkey = lineitem.l_partkey) AND (partsupp.ps_suppkey = lineitem.l_suppkey))
                                 Buffers: shared hit=843398 read=702079 written=2710
                                 ->  Index Scan using pk_partsupp on partsupp  (cost=0.00..603091.29 rows=8000000 width=12) (actual time=0.038..10315.627 rows=7999989 loops=1)
                                       Buffers: shared hit=289426 read=144783 written=2707
                                 ->  Sort  (cost=2720839.99..2728835.73 rows=3198298 width=28) (actual time=169081.106..171857.488 rows=3289434 loops=1)
                                       Sort Key: part.p_partkey, lineitem.l_suppkey
                                       Sort Method: quicksort  Memory: 355292kB
                                       Buffers: shared hit=553972 read=557296 written=3
                                       ->  Hash Join  (cost=66848.31..2375281.91 rows=3198298 width=28) (actual time=3629.284..163913.457 rows=3289434 loops=1)
                                             Hash Cond: (lineitem.l_partkey = part.p_partkey)
                                             Buffers: shared hit=553969 read=557296 written=3
                                             ->  Seq Scan on lineitem  (cost=0.00..1673595.31 rows=60285531 width=24) (actual time=0.045..43993.733 rows=60046221 loops=1)
                                                   Buffers: shared hit=544900 read=525840 written=3
                                             ->  Hash  (cost=65522.00..65522.00 rows=106105 width=4) (actual time=3629.031..3629.031 rows=109571 loops=1)
                                                   Buckets: 16384  Batches: 1  Memory Usage: 3853kB
                                                   Buffers: shared hit=9066 read=31456
                                                   ->  Seq Scan on part  (cost=0.00..65522.00 rows=106105 width=4) (actual time=0.041..3533.814 rows=109571 loops=1)
                                                         Filter: ((p_name)::text ~~ '%tomato%'::text)
                                                         Rows Removed by Filter: 1890429
                                                         Buffers: shared hit=9066 read=31456
                           ->  Index Scan using pk_supplier on supplier  (cost=0.00..0.28 rows=1 width=8) (actual time=0.013..0.013 rows=1 loops=3289434)
                                 Index Cond: (s_suppkey = lineitem.l_suppkey)
                                 Buffers: shared hit=9885451
                     ->  Index Only Scan using orders_o_orderkey_o_orderdate_idx on orders  (cost=0.00..1.95 rows=1 width=8) (actual time=0.037..0.037 rows=1 loops=3289434)
                           Index Cond: (o_orderkey = lineitem.l_orderkey)
                           Heap Fetches: 3289434
                           Buffers: shared hit=13047121 read=128539 dirtied=79 written=2207
               ->  Index Scan using pk_nation on nation  (cost=0.00..0.27 rows=1 width=30) (actual time=0.006..0.006 rows=1 loops=3289434)
                     Index Cond: (n_nationkey = supplier.s_nationkey)
                     Buffers: shared hit=6578868
 Total runtime: 414975.195 ms
(44 rows)

COMMIT;
COMMIT