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 '%beige%'
	) as profit
group by
	nation,
	o_year
order by
	nation,
	o_year desc;
                                                                                  QUERY PLAN                                                                                   
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 GroupAggregate  (cost=3492685.49..3492690.35 rows=139 width=46) (actual time=94523.627..96724.031 rows=175 loops=1)
   Buffers: shared hit=29954880 read=972865 written=7313
   ->  Sort  (cost=3492685.49..3492685.83 rows=139 width=46) (actual time=94514.989..94921.959 rows=3261224 loops=1)
         Sort Key: nation.n_name, (date_part('year'::text, (orders.o_orderdate)::timestamp without time zone))
         Sort Method: quicksort  Memory: 556914kB
         Buffers: shared hit=29954880 read=972865 written=7313
         ->  Nested Loop  (cost=2823092.81..3492680.54 rows=139 width=46) (actual time=34573.125..80536.180 rows=3261224 loops=1)
               Buffers: shared hit=29954872 read=972865 written=7313
               ->  Nested Loop  (cost=2823092.81..3492640.90 rows=139 width=24) (actual time=34573.014..74482.584 rows=3261224 loops=1)
                     Buffers: shared hit=23432424 read=972865 written=7313
                     ->  Nested Loop  (cost=2823092.81..3492370.10 rows=139 width=24) (actual time=34572.746..50570.321 rows=3261224 loops=1)
                           Buffers: shared hit=10664087 read=678517 written=1959
                           ->  Merge Join  (cost=2823092.81..3492329.62 rows=139 width=28) (actual time=34572.687..42762.096 rows=3261224 loops=1)
                                 Merge Cond: ((partsupp.ps_partkey = lineitem.l_partkey) AND (partsupp.ps_suppkey = lineitem.l_suppkey))
                                 Buffers: shared hit=862694 read=678517 written=1959
                                 ->  Index Scan using pk_partsupp on partsupp  (cost=0.00..603091.29 rows=8000000 width=12) (actual time=0.009..3886.781 rows=7999921 loops=1)
                                       Buffers: shared hit=416611 read=17597 written=1959
                                 ->  Sort  (cost=2823092.66..2831807.88 rows=3486086 width=28) (actual time=34572.428..36262.110 rows=3261224 loops=1)
                                       Sort Key: part.p_partkey, lineitem.l_suppkey
                                       Sort Method: quicksort  Memory: 353088kB
                                       Buffers: shared hit=446083 read=660920
                                       ->  Hash Join  (cost=66973.44..2444274.05 rows=3486086 width=28) (actual time=714.590..31989.695 rows=3261224 loops=1)
                                             Hash Cond: (lineitem.l_partkey = part.p_partkey)
                                             Buffers: shared hit=446080 read=660920
                                             ->  Seq Scan on lineitem  (cost=0.00..1666929.00 rows=60045400 width=24) (actual time=0.006..10965.049 rows=60045669 loops=1)
                                                   Buffers: shared hit=405555 read=660920
                                             ->  Hash  (cost=65522.00..65522.00 rows=116115 width=4) (actual time=714.427..714.427 rows=108590 loops=1)
                                                   Buckets: 16384  Batches: 1  Memory Usage: 3818kB
                                                   Buffers: shared hit=40522
                                                   ->  Seq Scan on part  (cost=0.00..65522.00 rows=116115 width=4) (actual time=0.018..687.358 rows=108590 loops=1)
                                                         Filter: ((p_name)::text ~~ '%beige%'::text)
                                                         Rows Removed by Filter: 1891410
                                                         Buffers: shared hit=40522
                           ->  Index Scan using pk_supplier on supplier  (cost=0.00..0.28 rows=1 width=8) (actual time=0.002..0.002 rows=1 loops=3261224)
                                 Index Cond: (s_suppkey = lineitem.l_suppkey)
                                 Buffers: shared hit=9801393
                     ->  Index Only Scan using orders_o_orderkey_o_orderdate_idx on orders  (cost=0.00..1.94 rows=1 width=8) (actual time=0.007..0.007 rows=1 loops=3261224)
                           Index Cond: (o_orderkey = lineitem.l_orderkey)
                           Heap Fetches: 3261224
                           Buffers: shared hit=12768337 read=294348 written=5354
               ->  Index Scan using pk_nation on nation  (cost=0.00..0.27 rows=1 width=30) (actual time=0.001..0.001 rows=1 loops=3261224)
                     Index Cond: (n_nationkey = supplier.s_nationkey)
                     Buffers: shared hit=6522448
 Total runtime: 96762.886 ms
(44 rows)

COMMIT;
COMMIT