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 '%lace%'
	) as profit
group by
	nation,
	o_year
order by
	nation,
	o_year desc;
                                                                                   QUERY PLAN                                                                                   
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 GroupAggregate  (cost=3377491.15..3377495.52 rows=125 width=46) (actual time=634708.299..638060.532 rows=175 loops=1)
   Buffers: shared hit=30130120 read=796434 dirtied=54 written=2104
   ->  Sort  (cost=3377491.15..3377491.46 rows=125 width=46) (actual time=634694.347..635610.974 rows=3260778 loops=1)
         Sort Key: nation.n_name, (date_part('year'::text, (orders.o_orderdate)::timestamp without time zone))
         Sort Method: quicksort  Memory: 556851kB
         Buffers: shared hit=30130120 read=796434 dirtied=54 written=2104
         ->  Nested Loop  (cost=2710566.89..3377486.80 rows=125 width=46) (actual time=196497.226..612227.849 rows=3260778 loops=1)
               Buffers: shared hit=30130112 read=796434 dirtied=54 written=2104
               ->  Nested Loop  (cost=2710566.89..3377451.15 rows=125 width=24) (actual time=196497.143..511994.350 rows=3260778 loops=1)
                     Buffers: shared hit=23608556 read=796434 dirtied=54 written=2104
                     ->  Nested Loop  (cost=2710566.89..3377206.39 rows=125 width=24) (actual time=196497.027..319024.951 rows=3260778 loops=1)
                           Buffers: shared hit=10647317 read=696692 written=702
                           ->  Merge Join  (cost=2710566.89..3377169.99 rows=125 width=28) (actual time=196496.622..217853.303 rows=3260778 loops=1)
                                 Merge Cond: ((partsupp.ps_partkey = lineitem.l_partkey) AND (partsupp.ps_suppkey = lineitem.l_suppkey))
                                 Buffers: shared hit=847710 read=696692 written=702
                                 ->  Index Scan using pk_partsupp on partsupp  (cost=0.00..603091.29 rows=8000000 width=12) (actual time=0.011..12629.250 rows=7999925 loops=1)
                                       Buffers: shared hit=388148 read=46060 written=698
                                 ->  Sort  (cost=2710566.87..2718403.74 rows=3134750 width=28) (actual time=196496.587..199942.296 rows=3260778 loops=1)
                                       Sort Key: part.p_partkey, lineitem.l_suppkey
                                       Sort Method: quicksort  Memory: 353053kB
                                       Buffers: shared hit=459562 read=650632 written=4
                                       ->  Hash Join  (cost=66823.27..2372328.61 rows=3134750 width=28) (actual time=3266.816..191403.720 rows=3260778 loops=1)
                                             Hash Cond: (lineitem.l_partkey = part.p_partkey)
                                             Buffers: shared hit=459559 read=650632 written=4
                                             ->  Seq Scan on lineitem  (cost=0.00..1671911.92 rows=60224592 width=24) (actual time=0.503..70347.582 rows=60045303 loops=1)
                                                   Buffers: shared hit=435161 read=634505 written=4
                                             ->  Hash  (cost=65522.00..65522.00 rows=104102 width=4) (actual time=3266.008..3266.008 rows=108577 loops=1)
                                                   Buckets: 16384  Batches: 1  Memory Usage: 3818kB
                                                   Buffers: shared hit=24395 read=16127
                                                   ->  Seq Scan on part  (cost=0.00..65522.00 rows=104102 width=4) (actual time=0.021..3181.269 rows=108577 loops=1)
                                                         Filter: ((p_name)::text ~~ '%lace%'::text)
                                                         Rows Removed by Filter: 1891423
                                                         Buffers: shared hit=24395 read=16127
                           ->  Index Scan using pk_supplier on supplier  (cost=0.00..0.28 rows=1 width=8) (actual time=0.029..0.030 rows=1 loops=3260778)
                                 Index Cond: (s_suppkey = lineitem.l_suppkey)
                                 Buffers: shared hit=9799607
                     ->  Index Scan using pk_orders on orders  (cost=0.00..1.95 rows=1 width=8) (actual time=0.057..0.058 rows=1 loops=3260778)
                           Index Cond: (o_orderkey = lineitem.l_orderkey)
                           Buffers: shared hit=12961239 read=99742 dirtied=54 written=1402
               ->  Index Scan using pk_nation on nation  (cost=0.00..0.27 rows=1 width=30) (actual time=0.027..0.028 rows=1 loops=3260778)
                     Index Cond: (n_nationkey = supplier.s_nationkey)
                     Buffers: shared hit=6521556
 Total runtime: 638185.976 ms
(43 rows)

COMMIT;
COMMIT