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 '%spring%'
	) as profit
group by
	nation,
	o_year
order by
	nation,
	o_year desc;
                                                                                  QUERY PLAN                                                                                   
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 GroupAggregate  (cost=3337487.26..3337491.25 rows=114 width=46) (actual time=321708.193..325324.832 rows=175 loops=1)
   Buffers: shared hit=30127035 read=1037746 dirtied=112 written=1965
   ->  Sort  (cost=3337487.26..3337487.55 rows=114 width=46) (actual time=321693.335..322765.732 rows=3287200 loops=1)
         Sort Key: nation.n_name, (date_part('year'::text, (orders.o_orderdate)::timestamp without time zone))
         Sort Method: quicksort  Memory: 560567kB
         Buffers: shared hit=30127035 read=1037746 dirtied=112 written=1965
         ->  Nested Loop  (cost=2672852.52..3337483.37 rows=114 width=46) (actual time=146972.861..298204.988 rows=3287200 loops=1)
               Buffers: shared hit=30127027 read=1037746 dirtied=112 written=1965
               ->  Nested Loop  (cost=2672852.52..3337450.86 rows=114 width=24) (actual time=146972.788..274221.801 rows=3287200 loops=1)
                     Buffers: shared hit=23552627 read=1037746 dirtied=112 written=1965
                     ->  Nested Loop  (cost=2672852.52..3337227.64 rows=114 width=24) (actual time=146972.736..189348.442 rows=3287200 loops=1)
                           Buffers: shared hit=10704578 read=718976 dirtied=3 written=680
                           ->  Merge Join  (cost=2672852.52..3337194.44 rows=114 width=28) (actual time=146972.674..161318.508 rows=3287200 loops=1)
                                 Merge Cond: ((partsupp.ps_partkey = lineitem.l_partkey) AND (partsupp.ps_suppkey = lineitem.l_suppkey))
                                 Buffers: shared hit=825427 read=718976 dirtied=3 written=680
                                 ->  Index Scan using pk_partsupp on partsupp  (cost=0.00..603091.29 rows=8000000 width=12) (actual time=0.018..6676.861 rows=7999977 loops=1)
                                       Buffers: shared hit=390969 read=43240 written=678
                                 ->  Sort  (cost=2672851.95..2679935.33 rows=2833352 width=28) (actual time=146972.624..150037.436 rows=3287200 loops=1)
                                       Sort Key: part.p_partkey, lineitem.l_suppkey
                                       Sort Method: quicksort  Memory: 355117kB
                                       Buffers: shared hit=434458 read=675736 dirtied=3 written=2
                                       ->  Hash Join  (cost=66698.15..2369200.51 rows=2833352 width=28) (actual time=2186.150..141142.461 rows=3287200 loops=1)
                                             Hash Cond: (lineitem.l_partkey = part.p_partkey)
                                             Buffers: shared hit=434455 read=675736 dirtied=3 written=2
                                             ->  Seq Scan on lineitem  (cost=0.00..1671917.42 rows=60225142 width=24) (actual time=0.049..31265.507 rows=60045303 loops=1)
                                                   Buffers: shared hit=425651 read=644015 dirtied=3 written=2
                                             ->  Hash  (cost=65522.00..65522.00 rows=94092 width=4) (actual time=2185.846..2185.846 rows=109488 loops=1)
                                                   Buckets: 16384  Batches: 1  Memory Usage: 3850kB
                                                   Buffers: shared hit=8801 read=31721
                                                   ->  Seq Scan on part  (cost=0.00..65522.00 rows=94092 width=4) (actual time=0.020..2096.173 rows=109488 loops=1)
                                                         Filter: ((p_name)::text ~~ '%spring%'::text)
                                                         Rows Removed by Filter: 1890512
                                                         Buffers: shared hit=8801 read=31721
                           ->  Index Scan using pk_supplier on supplier  (cost=0.00..0.28 rows=1 width=8) (actual time=0.007..0.007 rows=1 loops=3287200)
                                 Index Cond: (s_suppkey = lineitem.l_suppkey)
                                 Buffers: shared hit=9879151
                     ->  Index Scan using pk_orders on orders  (cost=0.00..1.95 rows=1 width=8) (actual time=0.024..0.025 rows=1 loops=3287200)
                           Index Cond: (o_orderkey = lineitem.l_orderkey)
                           Buffers: shared hit=12848049 read=318770 dirtied=109 written=1285
               ->  Index Scan using pk_nation on nation  (cost=0.00..0.27 rows=1 width=30) (actual time=0.005..0.005 rows=1 loops=3287200)
                     Index Cond: (n_nationkey = supplier.s_nationkey)
                     Buffers: shared hit=6574400
 Total runtime: 325461.576 ms
(43 rows)

COMMIT;
COMMIT