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 '%lawn%'
	) as profit
group by
	nation,
	o_year
order by
	nation,
	o_year desc;
                                                                                   QUERY PLAN                                                                                   
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 GroupAggregate  (cost=3240041.41..3240044.98 rows=102 width=46) (actual time=704922.505..708970.519 rows=175 loops=1)
   Buffers: shared hit=30277782 read=650024 dirtied=16 written=2163
   ->  Sort  (cost=3240041.41..3240041.67 rows=102 width=46) (actual time=704905.119..706141.668 rows=3260082 loops=1)
         Sort Key: nation.n_name, (date_part('year'::text, (orders.o_orderdate)::timestamp without time zone))
         Sort Method: quicksort  Memory: 556754kB
         Buffers: shared hit=30277782 read=650024 dirtied=16 written=2163
         ->  Nested Loop  (cost=2577563.31..3240038.01 rows=102 width=46) (actual time=188669.847..681968.479 rows=3260082 loops=1)
               Buffers: shared hit=30277774 read=650024 dirtied=16 written=2163
               ->  Nested Loop  (cost=2577563.31..3240008.92 rows=102 width=24) (actual time=188669.756..561067.572 rows=3260082 loops=1)
                     Buffers: shared hit=23757610 read=650024 dirtied=16 written=2163
                     ->  Nested Loop  (cost=2577563.31..3239806.85 rows=102 width=24) (actual time=188669.660..334504.404 rows=3260082 loops=1)
                           Buffers: shared hit=10812088 read=537600 written=865
                           ->  Merge Join  (cost=2577563.31..3239777.15 rows=102 width=28) (actual time=188669.598..213234.323 rows=3260082 loops=1)
                                 Merge Cond: ((partsupp.ps_partkey = lineitem.l_partkey) AND (partsupp.ps_suppkey = lineitem.l_suppkey))
                                 Buffers: shared hit=1014257 read=537600 written=865
                                 ->  Index Scan using pk_partsupp on partsupp  (cost=0.00..603091.29 rows=8000000 width=12) (actual time=0.044..16022.950 rows=7999993 loops=1)
                                       Buffers: shared hit=350935 read=83274 written=810
                                 ->  Sort  (cost=2577563.28..2583937.15 rows=2549546 width=28) (actual time=188669.465..191651.426 rows=3260082 loops=1)
                                       Sort Key: part.p_partkey, lineitem.l_suppkey
                                       Sort Method: quicksort  Memory: 352998kB
                                       Buffers: shared hit=663322 read=454326 written=55
                                       ->  Hash Join  (cost=66573.02..2306268.53 rows=2549546 width=28) (actual time=4075.545..184576.256 rows=3260082 loops=1)
                                             Hash Cond: (lineitem.l_partkey = part.p_partkey)
                                             Buffers: shared hit=663319 read=454326 written=55
                                             ->  Seq Scan on lineitem  (cost=0.00..1683562.69 rows=60644269 width=24) (actual time=0.027..62181.735 rows=60044872 loops=1)
                                                   Buffers: shared hit=662787 read=414333 written=2
                                             ->  Hash  (cost=65522.00..65522.00 rows=84082 width=4) (actual time=4075.206..4075.206 rows=108565 loops=1)
                                                   Buckets: 16384  Batches: 1  Memory Usage: 3817kB
                                                   Buffers: shared hit=529 read=39993 written=53
                                                   ->  Seq Scan on part  (cost=0.00..65522.00 rows=84082 width=4) (actual time=0.030..3987.881 rows=108565 loops=1)
                                                         Filter: ((p_name)::text ~~ '%lawn%'::text)
                                                         Rows Removed by Filter: 1891435
                                                         Buffers: shared hit=529 read=39993 written=53
                           ->  Index Scan using pk_supplier on supplier  (cost=0.00..0.28 rows=1 width=8) (actual time=0.035..0.036 rows=1 loops=3260082)
                                 Index Cond: (s_suppkey = lineitem.l_suppkey)
                                 Buffers: shared hit=9797831
                     ->  Index Scan using pk_orders on orders  (cost=0.00..1.97 rows=1 width=8) (actual time=0.068..0.068 rows=1 loops=3260082)
                           Index Cond: (o_orderkey = lineitem.l_orderkey)
                           Buffers: shared hit=12945522 read=112424 dirtied=16 written=1298
               ->  Index Scan using pk_nation on nation  (cost=0.00..0.27 rows=1 width=30) (actual time=0.034..0.034 rows=1 loops=3260082)
                     Index Cond: (n_nationkey = supplier.s_nationkey)
                     Buffers: shared hit=6520164
 Total runtime: 709108.474 ms
(43 rows)

COMMIT;
COMMIT