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 '%sandy%'
	) as profit
group by
	nation,
	o_year
order by
	nation,
	o_year desc;
                                                                                  QUERY PLAN                                                                                   
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 GroupAggregate  (cost=3345452.59..3345456.54 rows=113 width=46) (actual time=244571.419..247885.635 rows=175 loops=1)
   Buffers: shared hit=30373848 read=586410 written=1815
   ->  Sort  (cost=3345452.59..3345452.87 rows=113 width=46) (actual time=244559.298..245530.947 rows=3264137 loops=1)
         Sort Key: nation.n_name, (date_part('year'::text, (orders.o_orderdate)::timestamp without time zone))
         Sort Method: quicksort  Memory: 557324kB
         Buffers: shared hit=30373848 read=586410 written=1815
         ->  Nested Loop  (cost=2680751.93..3345448.73 rows=113 width=46) (actual time=121644.153..224792.016 rows=3264137 loops=1)
               Buffers: shared hit=30373840 read=586410 written=1815
               ->  Nested Loop  (cost=2680751.93..3345416.51 rows=113 width=24) (actual time=121644.087..207242.710 rows=3264137 loops=1)
                     Buffers: shared hit=23845566 read=586410 written=1815
                     ->  Nested Loop  (cost=2680751.93..3345194.13 rows=113 width=24) (actual time=121644.049..153848.043 rows=3264137 loops=1)
                           Buffers: shared hit=10777080 read=580634 written=1813
                           ->  Merge Join  (cost=2680751.93..3345161.23 rows=113 width=28) (actual time=121644.018..133891.010 rows=3264137 loops=1)
                                 Merge Cond: ((partsupp.ps_partkey = lineitem.l_partkey) AND (partsupp.ps_suppkey = lineitem.l_suppkey))
                                 Buffers: shared hit=966959 read=580634 written=1813
                                 ->  Index Scan using pk_partsupp on partsupp  (cost=0.00..603091.33 rows=8000000 width=12) (actual time=0.014..6026.912 rows=7999985 loops=1)
                                       Buffers: shared hit=338862 read=95347 written=1450
                                 ->  Sort  (cost=2680751.92..2687857.54 rows=2842250 width=28) (actual time=121643.903..123748.407 rows=3264137 loops=1)
                                       Sort Key: part.p_partkey, lineitem.l_suppkey
                                       Sort Method: quicksort  Memory: 353315kB
                                       Buffers: shared hit=628097 read=485287 written=363
                                       ->  Hash Join  (cost=66698.32..2376082.58 rows=2842250 width=28) (actual time=2005.380..117072.935 rows=3264137 loops=1)
                                             Hash Cond: (lineitem.l_partkey = part.p_partkey)
                                             Buffers: shared hit=628094 read=485287 written=363
                                             ->  Seq Scan on lineitem  (cost=0.00..1676908.88 rows=60405288 width=24) (actual time=0.041..23610.822 rows=60045310 loops=1)
                                                   Buffers: shared hit=627924 read=444932
                                             ->  Hash  (cost=65522.00..65522.00 rows=94106 width=4) (actual time=2004.621..2004.621 rows=108733 loops=1)
                                                   Buckets: 16384  Batches: 1  Memory Usage: 3823kB
                                                   Buffers: shared hit=167 read=40355 written=363
                                                   ->  Seq Scan on part  (cost=0.00..65522.00 rows=94106 width=4) (actual time=0.035..1930.960 rows=108733 loops=1)
                                                         Filter: ((p_name)::text ~~ '%sandy%'::text)
                                                         Rows Removed by Filter: 1891267
                                                         Buffers: shared hit=167 read=40355 written=363
                           ->  Index Scan using pk_supplier on supplier  (cost=0.00..0.28 rows=1 width=8) (actual time=0.005..0.005 rows=1 loops=3264137)
                                 Index Cond: (s_suppkey = lineitem.l_suppkey)
                                 Buffers: shared hit=9810121
                     ->  Index Scan using pk_orders on orders  (cost=0.00..1.96 rows=1 width=8) (actual time=0.015..0.015 rows=1 loops=3264137)
                           Index Cond: (o_orderkey = lineitem.l_orderkey)
                           Buffers: shared hit=13068486 read=5776 written=2
               ->  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=3264137)
                     Index Cond: (n_nationkey = supplier.s_nationkey)
                     Buffers: shared hit=6528274
 Total runtime: 247975.681 ms
(43 rows)

COMMIT;
COMMIT