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 '%hot%'
	) as profit
group by
	nation,
	o_year
order by
	nation,
	o_year desc;
                                                                                  QUERY PLAN                                                                                   
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 GroupAggregate  (cost=3374742.83..3374747.03 rows=120 width=46) (actual time=415500.046..419201.061 rows=175 loops=1)
   Buffers: shared hit=30485579 read=503984 dirtied=33 written=1802
   ->  Sort  (cost=3374742.83..3374743.13 rows=120 width=46) (actual time=415484.152..416604.066 rows=3267129 loops=1)
         Sort Key: nation.n_name, (date_part('year'::text, (orders.o_orderdate)::timestamp without time zone))
         Sort Method: quicksort  Memory: 557745kB
         Buffers: shared hit=30485579 read=503984 dirtied=33 written=1802
         ->  Nested Loop  (cost=2708622.61..3374738.69 rows=120 width=46) (actual time=132070.393..393648.604 rows=3267129 loops=1)
               Buffers: shared hit=30485571 read=503984 dirtied=33 written=1802
               ->  Nested Loop  (cost=2708622.61..3374704.47 rows=120 width=24) (actual time=132070.305..360664.593 rows=3267129 loops=1)
                     Buffers: shared hit=23951313 read=503984 dirtied=33 written=1802
                     ->  Nested Loop  (cost=2708622.61..3374467.53 rows=120 width=24) (actual time=132070.180..209602.377 rows=3267129 loops=1)
                           Buffers: shared hit=11046062 read=322698 written=140
                           ->  Merge Join  (cost=2708622.61..3374432.58 rows=120 width=28) (actual time=132070.125..149442.589 rows=3267129 loops=1)
                                 Merge Cond: ((partsupp.ps_partkey = lineitem.l_partkey) AND (partsupp.ps_suppkey = lineitem.l_suppkey))
                                 Buffers: shared hit=1227014 read=322698 written=140
                                 ->  Index Scan using pk_partsupp on partsupp  (cost=0.00..603091.29 rows=8000000 width=12) (actual time=0.016..9376.359 rows=7999945 loops=1)
                                       Buffers: shared hit=379178 read=55030 written=140
                                 ->  Sort  (cost=2708622.48..2716195.47 rows=3029197 width=28) (actual time=132069.905..135015.376 rows=3267129 loops=1)
                                       Sort Key: part.p_partkey, lineitem.l_suppkey
                                       Sort Method: quicksort  Memory: 353549kB
                                       Buffers: shared hit=847836 read=267668
                                       ->  Hash Join  (cost=66773.24..2382521.79 rows=3029197 width=28) (actual time=2825.889..126565.542 rows=3267129 loops=1)
                                             Hash Cond: (lineitem.l_partkey = part.p_partkey)
                                             Buffers: shared hit=847833 read=267668
                                             ->  Seq Scan on lineitem  (cost=0.00..1680216.29 rows=60524029 width=24) (actual time=0.027..28698.687 rows=60044082 loops=1)
                                                   Buffers: shared hit=842074 read=232902
                                             ->  Hash  (cost=65522.00..65522.00 rows=100099 width=4) (actual time=2825.453..2825.453 rows=108843 loops=1)
                                                   Buckets: 16384  Batches: 1  Memory Usage: 3827kB
                                                   Buffers: shared hit=5756 read=34766
                                                   ->  Seq Scan on part  (cost=0.00..65522.00 rows=100099 width=4) (actual time=0.124..2729.801 rows=108843 loops=1)
                                                         Filter: ((p_name)::text ~~ '%hot%'::text)
                                                         Rows Removed by Filter: 1891157
                                                         Buffers: shared hit=5756 read=34766
                           ->  Index Scan using pk_supplier on supplier  (cost=0.00..0.28 rows=1 width=8) (actual time=0.017..0.017 rows=1 loops=3267129)
                                 Index Cond: (s_suppkey = lineitem.l_suppkey)
                                 Buffers: shared hit=9819048
                     ->  Index Only Scan using orders_o_orderkey_o_orderdate_idx on orders  (cost=0.00..1.96 rows=1 width=8) (actual time=0.045..0.045 rows=1 loops=3267129)
                           Index Cond: (o_orderkey = lineitem.l_orderkey)
                           Heap Fetches: 3267129
                           Buffers: shared hit=12905251 read=181286 dirtied=33 written=1662
               ->  Index Scan using pk_nation on nation  (cost=0.00..0.27 rows=1 width=30) (actual time=0.007..0.008 rows=1 loops=3267129)
                     Index Cond: (n_nationkey = supplier.s_nationkey)
                     Buffers: shared hit=6534258
 Total runtime: 419304.550 ms
(44 rows)

COMMIT;
COMMIT