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 '%olive%'
	) as profit
group by
	nation,
	o_year
order by
	nation,
	o_year desc;
                                                                                  QUERY PLAN                                                                                   
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 GroupAggregate  (cost=3396254.56..3396258.97 rows=126 width=46) (actual time=249282.788..252681.210 rows=175 loops=1)
   Buffers: shared hit=29792388 read=993595 dirtied=40 written=6149
   ->  Sort  (cost=3396254.56..3396254.88 rows=126 width=46) (actual time=249238.865..250227.206 rows=3244308 loops=1)
         Sort Key: nation.n_name, (date_part('year'::text, (orders.o_orderdate)::timestamp without time zone))
         Sort Method: quicksort  Memory: 554535kB
         Buffers: shared hit=29792388 read=993595 dirtied=40 written=6149
         ->  Nested Loop  (cost=2729161.82..3396250.16 rows=126 width=46) (actual time=116900.584..226478.326 rows=3244308 loops=1)
               Buffers: shared hit=29792380 read=993595 dirtied=40 written=6149
               ->  Nested Loop  (cost=2729161.82..3396214.23 rows=126 width=24) (actual time=116900.521..210018.066 rows=3244308 loops=1)
                     Buffers: shared hit=23303764 read=993595 dirtied=40 written=6149
                     ->  Nested Loop  (cost=2729161.82..3395964.61 rows=126 width=24) (actual time=116900.426..147930.529 rows=3244308 loops=1)
                           Buffers: shared hit=10515257 read=787233 written=1828
                           ->  Merge Join  (cost=2729161.82..3395927.92 rows=126 width=28) (actual time=116900.380..129000.518 rows=3244308 loops=1)
                                 Merge Cond: ((partsupp.ps_partkey = lineitem.l_partkey) AND (partsupp.ps_suppkey = lineitem.l_suppkey))
                                 Buffers: shared hit=764617 read=787233 written=1828
                                 ->  Index Scan using pk_partsupp on partsupp  (cost=0.00..603091.33 rows=8000000 width=12) (actual time=0.008..5654.141 rows=7999861 loops=1)
                                       Buffers: shared hit=317147 read=117055 written=1826
                                 ->  Sort  (cost=2729161.71..2737053.27 rows=3156622 width=28) (actual time=116900.244..119303.706 rows=3244308 loops=1)
                                       Sort Key: part.p_partkey, lineitem.l_suppkey
                                       Sort Method: quicksort  Memory: 351766kB
                                       Buffers: shared hit=447470 read=670178 written=2
                                       ->  Hash Join  (cost=66823.27..2388405.16 rows=3156622 width=28) (actual time=1808.694..111765.451 rows=3244308 loops=1)
                                             Hash Cond: (lineitem.l_partkey = part.p_partkey)
                                             Buffers: shared hit=447467 read=670178 written=2
                                             ->  Seq Scan on lineitem  (cost=0.00..1683567.83 rows=60644783 width=24) (actual time=0.027..22994.715 rows=60044872 loops=1)
                                                   Buffers: shared hit=424761 read=652359 written=2
                                             ->  Hash  (cost=65522.00..65522.00 rows=104102 width=4) (actual time=1808.540..1808.540 rows=108018 loops=1)
                                                   Buckets: 16384  Batches: 1  Memory Usage: 3798kB
                                                   Buffers: shared hit=22703 read=17819
                                                   ->  Seq Scan on part  (cost=0.00..65522.00 rows=104102 width=4) (actual time=0.020..1740.550 rows=108018 loops=1)
                                                         Filter: ((p_name)::text ~~ '%olive%'::text)
                                                         Rows Removed by Filter: 1891982
                                                         Buffers: shared hit=22703 read=17819
                           ->  Index Scan using pk_supplier on supplier  (cost=0.00..0.28 rows=1 width=8) (actual time=0.004..0.005 rows=1 loops=3244308)
                                 Index Cond: (s_suppkey = lineitem.l_suppkey)
                                 Buffers: shared hit=9750640
                     ->  Index Only Scan using orders_o_orderkey_o_orderdate_idx on orders  (cost=0.00..1.97 rows=1 width=8) (actual time=0.018..0.018 rows=1 loops=3244308)
                           Index Cond: (o_orderkey = lineitem.l_orderkey)
                           Heap Fetches: 3244308
                           Buffers: shared hit=12788507 read=206362 dirtied=40 written=4321
               ->  Index Scan using pk_nation on nation  (cost=0.00..0.27 rows=1 width=30) (actual time=0.003..0.003 rows=1 loops=3244308)
                     Index Cond: (n_nationkey = supplier.s_nationkey)
                     Buffers: shared hit=6488616
 Total runtime: 252794.639 ms
(44 rows)

COMMIT;
COMMIT