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 '%rose%'
	) as profit
group by
	nation,
	o_year
order by
	nation,
	o_year desc;
                                                                                  QUERY PLAN                                                                                   
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 GroupAggregate  (cost=3385438.90..3385443.14 rows=121 width=46) (actual time=238241.605..241285.527 rows=175 loops=1)
   Buffers: shared hit=29995968 read=903889 dirtied=137 written=7401
   ->  Sort  (cost=3385438.90..3385439.21 rows=121 width=46) (actual time=238230.004..239125.981 rows=3256821 loops=1)
         Sort Key: nation.n_name, (date_part('year'::text, (orders.o_orderdate)::timestamp without time zone))
         Sort Method: quicksort  Memory: 556295kB
         Buffers: shared hit=29995968 read=903889 dirtied=137 written=7401
         ->  Nested Loop  (cost=2719227.39..3385434.72 rows=121 width=46) (actual time=109261.714..218314.654 rows=3256821 loops=1)
               Buffers: shared hit=29995960 read=903889 dirtied=137 written=7401
               ->  Nested Loop  (cost=2719227.39..3385400.21 rows=121 width=24) (actual time=109261.633..202406.047 rows=3256821 loops=1)
                     Buffers: shared hit=23482318 read=903889 dirtied=137 written=7401
                     ->  Nested Loop  (cost=2719227.39..3385159.70 rows=121 width=24) (actual time=109261.510..140120.710 rows=3256821 loops=1)
                           Buffers: shared hit=10672486 read=668860 written=1971
                           ->  Merge Join  (cost=2719227.39..3385124.46 rows=121 width=28) (actual time=109261.458..121558.983 rows=3256821 loops=1)
                                 Merge Cond: ((partsupp.ps_partkey = lineitem.l_partkey) AND (partsupp.ps_suppkey = lineitem.l_suppkey))
                                 Buffers: shared hit=885731 read=668268 written=1971
                                 ->  Index Scan using pk_partsupp on partsupp  (cost=0.00..603091.29 rows=8000000 width=12) (actual time=0.008..5928.196 rows=7999957 loops=1)
                                       Buffers: shared hit=273241 read=160968 written=1969
                                 ->  Sort  (cost=2719227.39..2726830.38 rows=3041199 width=28) (actual time=109261.364..111513.014 rows=3256821 loops=1)
                                       Sort Key: part.p_partkey, lineitem.l_suppkey
                                       Sort Method: quicksort  Memory: 352744kB
                                       Buffers: shared hit=612490 read=507300 written=2
                                       ->  Hash Join  (cost=66773.21..2391747.90 rows=3041199 width=28) (actual time=1320.152..105392.783 rows=3256821 loops=1)
                                             Hash Cond: (lineitem.l_partkey = part.p_partkey)
                                             Buffers: shared hit=612487 read=507300 written=2
                                             ->  Seq Scan on lineitem  (cost=0.00..1686912.35 rows=60765035 width=24) (actual time=0.020..18967.375 rows=60045297 loops=1)
                                                   Buffers: shared hit=575787 read=503475 written=2
                                             ->  Hash  (cost=65522.00..65522.00 rows=100097 width=4) (actual time=1319.708..1319.708 rows=108458 loops=1)
                                                   Buckets: 16384  Batches: 1  Memory Usage: 3813kB
                                                   Buffers: shared hit=36697 read=3825
                                                   ->  Seq Scan on part  (cost=0.00..65522.00 rows=100097 width=4) (actual time=0.021..1259.673 rows=108458 loops=1)
                                                         Filter: ((p_name)::text ~~ '%rose%'::text)
                                                         Rows Removed by Filter: 1891542
                                                         Buffers: shared hit=36697 read=3825
                           ->  Index Scan using pk_supplier on supplier  (cost=0.00..0.28 rows=1 width=8) (actual time=0.004..0.005 rows=1 loops=3256821)
                                 Index Cond: (s_suppkey = lineitem.l_suppkey)
                                 Buffers: shared hit=9786755 read=592
                     ->  Index Only Scan using orders_o_orderkey_o_orderdate_idx on orders  (cost=0.00..1.98 rows=1 width=8) (actual time=0.018..0.018 rows=1 loops=3256821)
                           Index Cond: (o_orderkey = lineitem.l_orderkey)
                           Heap Fetches: 3256821
                           Buffers: shared hit=12809832 read=235029 dirtied=137 written=5430
               ->  Index Scan using pk_nation on nation  (cost=0.00..0.27 rows=1 width=30) (actual time=0.003..0.003 rows=1 loops=3256821)
                     Index Cond: (n_nationkey = supplier.s_nationkey)
                     Buffers: shared hit=6513642
 Total runtime: 241413.169 ms
(44 rows)

COMMIT;
COMMIT