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 '%khaki%'
	) as profit
group by
	nation,
	o_year
order by
	nation,
	o_year desc;
                                                                                           QUERY PLAN                                                                                            
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 GroupAggregate  (cost=1230842.62..1230847.38 rows=136 width=46) (actual time=116893.135..120066.764 rows=175 loops=1)
   Group Key: nation.n_name, (date_part('year'::text, (orders.o_orderdate)::timestamp without time zone))
   Buffers: shared hit=35684400 read=2307914 dirtied=13224 written=18791
   ->  Sort  (cost=1230842.62..1230842.96 rows=136 width=46) (actual time=116881.912..117856.546 rows=3263552 loops=1)
         Sort Key: nation.n_name, (date_part('year'::text, (orders.o_orderdate)::timestamp without time zone))
         Sort Method: quicksort  Memory: 557242kB
         Buffers: shared hit=35684400 read=2307914 dirtied=13224 written=18791
         ->  Hash Join  (cost=66926.24..1230837.81 rows=136 width=46) (actual time=1030.559..103121.174 rows=3263552 loops=1)
               Hash Cond: (supplier.s_nationkey = nation.n_nationkey)
               Buffers: shared hit=35684392 read=2307914 dirtied=13224 written=18791
               ->  Nested Loop  (cost=66924.68..1230833.69 rows=136 width=24) (actual time=1030.496..99962.323 rows=3263552 loops=1)
                     Buffers: shared hit=35684388 read=2307914 dirtied=13224 written=18791
                     ->  Nested Loop  (cost=66924.24..1230767.78 rows=136 width=24) (actual time=1030.391..53208.773 rows=3263552 loops=1)
                           Buffers: shared hit=23361868 read=1558443 dirtied=12892 written=10847
                           ->  Nested Loop  (cost=66923.95..1230723.90 rows=136 width=28) (actual time=1030.379..41006.465 rows=3263552 loops=1)
                                 Buffers: shared hit=13553283 read=1558443 dirtied=12892 written=10847
                                 ->  Hash Join  (cost=66923.39..352365.83 rows=448444 width=16) (actual time=1030.293..5648.210 rows=435100 loops=1)
                                       Hash Cond: (partsupp.ps_partkey = part.p_partkey)
                                       Buffers: shared hit=70886 read=140594 written=742
                                       ->  Seq Scan on partsupp  (cost=0.00..250958.00 rows=8000000 width=12) (actual time=0.010..2528.992 rows=8000000 loops=1)
                                             Buffers: shared hit=68486 read=102472 written=656
                                       ->  Hash  (cost=65522.00..65522.00 rows=112111 width=4) (actual time=1029.509..1029.509 rows=108775 loops=1)
                                             Buckets: 131072  Batches: 1  Memory Usage: 4849kB
                                             Buffers: shared hit=2400 read=38122 written=86
                                             ->  Seq Scan on part  (cost=0.00..65522.00 rows=112111 width=4) (actual time=0.017..985.574 rows=108775 loops=1)
                                                   Filter: ((p_name)::text ~~ '%khaki%'::text)
                                                   Rows Removed by Filter: 1891225
                                                   Buffers: shared hit=2400 read=38122 written=86
                                 ->  Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem  (cost=0.56..1.95 rows=1 width=24) (actual time=0.016..0.079 rows=8 loops=435100)
                                       Index Cond: (l_partkey = partsupp.ps_partkey)
                                       Filter: (partsupp.ps_suppkey = l_suppkey)
                                       Rows Removed by Filter: 23
                                       Buffers: shared hit=13482397 read=1417849 dirtied=12892 written=10105
                           ->  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=3263552)
                                 Index Cond: (s_suppkey = lineitem.l_suppkey)
                                 Buffers: shared hit=9808585
                     ->  Index Only Scan using orders_o_orderkey_o_orderdate_idx on orders  (cost=0.43..0.47 rows=1 width=8) (actual time=0.013..0.014 rows=1 loops=3263552)
                           Index Cond: (o_orderkey = lineitem.l_orderkey)
                           Heap Fetches: 3263552
                           Buffers: shared hit=12322520 read=749471 dirtied=332 written=7944
               ->  Hash  (cost=1.25..1.25 rows=25 width=30) (actual time=0.022..0.022 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..0.009 rows=25 loops=1)
                           Buffers: shared hit=1
 Planning time: 32.953 ms
 Execution time: 120125.525 ms
(47 rows)

COMMIT;
COMMIT