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 '%gainsboro%'
	) as profit
group by
	nation,
	o_year
order by
	nation,
	o_year desc;
                                                                                           QUERY PLAN                                                                                            
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 GroupAggregate  (cost=1167657.65..1167662.06 rows=126 width=46) (actual time=132491.889..135931.492 rows=175 loops=1)
   Group Key: nation.n_name, (date_part('year'::text, (orders.o_orderdate)::timestamp without time zone))
   Buffers: shared hit=35412230 read=2362130 dirtied=13714 written=15965
   ->  Sort  (cost=1167657.65..1167657.96 rows=126 width=46) (actual time=132478.905..133660.123 rows=3245136 loops=1)
         Sort Key: nation.n_name, (date_part('year'::text, (orders.o_orderdate)::timestamp without time zone))
         Sort Method: quicksort  Memory: 554652kB
         Buffers: shared hit=35412230 read=2362130 dirtied=13714 written=15965
         ->  Hash Join  (cost=66826.12..1167653.25 rows=126 width=46) (actual time=1353.182..121215.626 rows=3245136 loops=1)
               Hash Cond: (supplier.s_nationkey = nation.n_nationkey)
               Buffers: shared hit=35412222 read=2362130 dirtied=13714 written=15965
               ->  Nested Loop  (cost=66824.55..1167649.33 rows=126 width=24) (actual time=1353.088..117206.852 rows=3245136 loops=1)
                     Buffers: shared hit=35412218 read=2362130 dirtied=13714 written=15965
                     ->  Nested Loop  (cost=66824.12..1167588.26 rows=126 width=24) (actual time=1352.958..61551.980 rows=3245136 loops=1)
                           Buffers: shared hit=23223516 read=1552687 dirtied=13243 written=9931
                           ->  Nested Loop  (cost=66823.83..1167547.28 rows=127 width=28) (actual time=1352.935..47715.195 rows=3245136 loops=1)
                                 Buffers: shared hit=13469979 read=1552687 dirtied=13243 written=9931
                                 ->  Hash Join  (cost=66823.26..351945.30 rows=416404 width=16) (actual time=1352.758..6999.750 rows=432148 loops=1)
                                       Hash Cond: (partsupp.ps_partkey = part.p_partkey)
                                       Buffers: shared hit=72416 read=139064 written=880
                                       ->  Seq Scan on partsupp  (cost=0.00..250958.00 rows=8000000 width=12) (actual time=0.010..2982.924 rows=8000000 loops=1)
                                             Buffers: shared hit=66906 read=104052 written=720
                                       ->  Hash  (cost=65522.00..65522.00 rows=104101 width=4) (actual time=1351.807..1351.807 rows=108037 loops=1)
                                             Buckets: 131072  Batches: 1  Memory Usage: 4823kB
                                             Buffers: shared hit=5510 read=35012 written=160
                                             ->  Seq Scan on part  (cost=0.00..65522.00 rows=104101 width=4) (actual time=0.025..1285.717 rows=108037 loops=1)
                                                   Filter: ((p_name)::text ~~ '%gainsboro%'::text)
                                                   Rows Removed by Filter: 1891963
                                                   Buffers: shared hit=5510 read=35012 written=160
                                 ->  Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem  (cost=0.56..1.95 rows=1 width=24) (actual time=0.019..0.091 rows=8 loops=432148)
                                       Index Cond: (l_partkey = partsupp.ps_partkey)
                                       Filter: (partsupp.ps_suppkey = l_suppkey)
                                       Rows Removed by Filter: 23
                                       Buffers: shared hit=13397563 read=1413623 dirtied=13243 written=9051
                           ->  Index Scan using pk_supplier on supplier  (cost=0.29..0.31 rows=1 width=8) (actual time=0.003..0.003 rows=1 loops=3245136)
                                 Index Cond: (s_suppkey = lineitem.l_suppkey)
                                 Buffers: shared hit=9753537
                     ->  Index Only Scan using orders_o_orderkey_o_orderdate_idx on orders  (cost=0.43..0.47 rows=1 width=8) (actual time=0.016..0.016 rows=1 loops=3245136)
                           Index Cond: (o_orderkey = lineitem.l_orderkey)
                           Heap Fetches: 3245136
                           Buffers: shared hit=12188702 read=809443 dirtied=471 written=6034
               ->  Hash  (cost=1.25..1.25 rows=25 width=30) (actual time=0.028..0.028 rows=25 loops=1)
                     Buckets: 1024  Batches: 1  Memory Usage: 10kB
                     Buffers: shared hit=1
                     ->  Seq Scan on nation  (cost=0.00..1.25 rows=25 width=30) (actual time=0.007..0.013 rows=25 loops=1)
                           Buffers: shared hit=1
 Planning time: 55.625 ms
 Execution time: 135982.701 ms
(47 rows)

COMMIT;
COMMIT