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 '%royal%'
	) as profit
group by
	nation,
	o_year
order by
	nation,
	o_year desc;
                                                                                           QUERY PLAN                                                                                            
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 GroupAggregate  (cost=1294614.03..1294619.14 rows=146 width=46) (actual time=130943.132..134425.613 rows=175 loops=1)
   Group Key: nation.n_name, (date_part('year'::text, (orders.o_orderdate)::timestamp without time zone))
   Buffers: shared hit=35627648 read=2413192 dirtied=13454 written=14762
   ->  Sort  (cost=1294614.03..1294614.40 rows=146 width=46) (actual time=130931.430..132181.067 rows=3267801 loops=1)
         Sort Key: nation.n_name, (date_part('year'::text, (orders.o_orderdate)::timestamp without time zone))
         Sort Method: quicksort  Memory: 557839kB
         Buffers: shared hit=35627648 read=2413192 dirtied=13454 written=14762
         ->  Hash Join  (cost=67026.48..1294608.78 rows=146 width=46) (actual time=1721.232..117230.895 rows=3267801 loops=1)
               Hash Cond: (supplier.s_nationkey = nation.n_nationkey)
               Buffers: shared hit=35627640 read=2413192 dirtied=13454 written=14762
               ->  Nested Loop  (cost=67024.92..1294604.48 rows=146 width=24) (actual time=1721.140..112886.177 rows=3267801 loops=1)
                     Buffers: shared hit=35627636 read=2413192 dirtied=13454 written=14762
                     ->  Nested Loop  (cost=67024.48..1294533.72 rows=146 width=24) (actual time=1721.028..59991.940 rows=3267801 loops=1)
                           Buffers: shared hit=23387245 read=1564387 dirtied=13369 written=10787
                           ->  Nested Loop  (cost=67024.19..1294486.62 rows=146 width=28) (actual time=1721.007..46301.760 rows=3267801 loops=1)
                                 Buffers: shared hit=13565758 read=1564387 dirtied=13369 written=10787
                                 ->  Hash Join  (cost=67023.62..352786.83 rows=480520 width=16) (actual time=1720.944..6783.467 rows=435220 loops=1)
                                       Hash Cond: (partsupp.ps_partkey = part.p_partkey)
                                       Buffers: shared hit=91099 read=120381 written=136
                                       ->  Seq Scan on partsupp  (cost=0.00..250958.00 rows=8000000 width=12) (actual time=0.014..2696.994 rows=8000000 loops=1)
                                             Buffers: shared hit=91096 read=79862 written=135
                                       ->  Hash  (cost=65522.00..65522.00 rows=120130 width=4) (actual time=1720.063..1720.063 rows=108805 loops=1)
                                             Buckets: 131072  Batches: 1  Memory Usage: 4850kB
                                             Buffers: shared hit=3 read=40519 written=1
                                             ->  Seq Scan on part  (cost=0.00..65522.00 rows=120130 width=4) (actual time=0.017..1636.072 rows=108805 loops=1)
                                                   Filter: ((p_name)::text ~~ '%royal%'::text)
                                                   Rows Removed by Filter: 1891195
                                                   Buffers: shared hit=3 read=40519 written=1
                                 ->  Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem  (cost=0.56..1.95 rows=1 width=24) (actual time=0.018..0.087 rows=8 loops=435220)
                                       Index Cond: (l_partkey = partsupp.ps_partkey)
                                       Filter: (partsupp.ps_suppkey = l_suppkey)
                                       Rows Removed by Filter: 23
                                       Buffers: shared hit=13474659 read=1444006 dirtied=13369 written=10651
                           ->  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=3267801)
                                 Index Cond: (s_suppkey = lineitem.l_suppkey)
                                 Buffers: shared hit=9821487
                     ->  Index Only Scan using orders_o_orderkey_o_orderdate_idx on orders  (cost=0.43..0.47 rows=1 width=8) (actual time=0.015..0.015 rows=1 loops=3267801)
                           Index Cond: (o_orderkey = lineitem.l_orderkey)
                           Heap Fetches: 3267801
                           Buffers: shared hit=12240391 read=848805 dirtied=85 written=3975
               ->  Hash  (cost=1.25..1.25 rows=25 width=30) (actual time=0.031..0.031 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=0.006..0.014 rows=25 loops=1)
                           Buffers: shared hit=1
 Planning time: 54.524 ms
 Execution time: 134472.167 ms
(47 rows)

COMMIT;
COMMIT