BEGIN;
BEGIN
EXPLAIN (ANALYZE, BUFFERS)
select
	supp_nation,
	cust_nation,
	l_year,
	sum(volume) as revenue
from
	(
		select
			n1.n_name as supp_nation,
			n2.n_name as cust_nation,
			extract(year from l_shipdate) as l_year,
			l_extendedprice * (1 - l_discount) as volume
		from
			supplier,
			lineitem,
			orders,
			customer,
			nation n1,
			nation n2
		where
			s_suppkey = l_suppkey
			and o_orderkey = l_orderkey
			and c_custkey = o_custkey
			and s_nationkey = n1.n_nationkey
			and c_nationkey = n2.n_nationkey
			and (
				(n1.n_name = 'GERMANY' and n2.n_name = 'ARGENTINA')
				or (n1.n_name = 'ARGENTINA' and n2.n_name = 'GERMANY')
			)
			and l_shipdate between date '1995-01-01' and date '1996-12-31'
	) as shipping
group by
	supp_nation,
	cust_nation,
	l_year
order by
	supp_nation,
	cust_nation,
	l_year;
                                                                                       QUERY PLAN                                                                                        
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Sort  (cost=2001949.16..2001956.87 rows=3085 width=64) (actual time=21883.477..21883.478 rows=4 loops=1)
   Sort Key: n1.n_name, n2.n_name, (date_part('year'::text, (lineitem.l_shipdate)::timestamp without time zone))
   Sort Method: quicksort  Memory: 25kB
   Buffers: shared hit=4799691 read=734516 written=4
   ->  HashAggregate  (cost=2001724.09..2001770.36 rows=3085 width=64) (actual time=21883.392..21883.403 rows=4 loops=1)
         Group Key: n1.n_name, n2.n_name, date_part('year'::text, (lineitem.l_shipdate)::timestamp without time zone)
         Buffers: shared hit=4799683 read=734516 written=4
         ->  Hash Join  (cost=62340.37..2000806.27 rows=61188 width=64) (actual time=953.077..21800.579 rows=58667 loops=1)
               Hash Cond: (lineitem.l_suppkey = supplier.s_suppkey)
               Join Filter: (((n1.n_name = 'GERMANY'::bpchar) AND (n2.n_name = 'ARGENTINA'::bpchar)) OR ((n1.n_name = 'ARGENTINA'::bpchar) AND (n2.n_name = 'GERMANY'::bpchar)))
               Rows Removed by Join Filter: 58954
               Buffers: shared hit=4799683 read=734516 written=4
               ->  Nested Loop  (cost=58604.97..1988898.77 rows=1470308 width=42) (actual time=892.528..20903.743 rows=1462648 loops=1)
                     Buffers: shared hit=4799622 read=732394 written=4
                     ->  Hash Join  (cost=58604.40..531536.45 rows=1203596 width=30) (actual time=892.455..11519.305 rows=1200690 loops=1)
                           Hash Cond: (orders.o_custkey = customer.c_custkey)
                           Buffers: shared hit=65 read=289242 written=4
                           ->  Seq Scan on orders  (cost=0.00..404477.52 rows=15044952 width=8) (actual time=0.009..3935.654 rows=15000000 loops=1)
                                 Buffers: shared hit=13 read=254015
                           ->  Hash  (cost=57104.40..57104.40 rows=120000 width=30) (actual time=891.784..891.784 rows=119994 loops=1)
                                 Buckets: 131072  Batches: 1  Memory Usage: 8290kB
                                 Buffers: shared hit=52 read=35227 written=4
                                 ->  Hash Join  (cost=1.40..57104.40 rows=120000 width=30) (actual time=0.055..843.947 rows=119994 loops=1)
                                       Hash Cond: (customer.c_nationkey = n2.n_nationkey)
                                       Buffers: shared hit=52 read=35227 written=4
                                       ->  Seq Scan on customer  (cost=0.00..50278.00 rows=1500000 width=8) (actual time=0.013..622.815 rows=1500000 loops=1)
                                             Buffers: shared hit=51 read=35227 written=4
                                       ->  Hash  (cost=1.38..1.38 rows=2 width=30) (actual time=0.028..0.028 rows=2 loops=1)
                                             Buckets: 1024  Batches: 1  Memory Usage: 9kB
                                             Buffers: shared hit=1
                                             ->  Seq Scan on nation n2  (cost=0.00..1.38 rows=2 width=30) (actual time=0.015..0.021 rows=2 loops=1)
                                                   Filter: ((n_name = 'ARGENTINA'::bpchar) OR (n_name = 'GERMANY'::bpchar))
                                                   Rows Removed by Filter: 23
                                                   Buffers: shared hit=1
                     ->  Index Scan using lineitem_l_orderkey_l_linenumber_l_shipdate_idx on lineitem  (cost=0.56..1.16 rows=5 width=20) (actual time=0.007..0.007 rows=1 loops=1200690)
                           Index Cond: ((l_orderkey = orders.o_orderkey) AND (l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date))
                           Buffers: shared hit=4799557 read=443152
               ->  Hash  (cost=3635.40..3635.40 rows=8000 width=30) (actual time=60.465..60.465 rows=8056 loops=1)
                     Buckets: 8192  Batches: 1  Memory Usage: 552kB
                     Buffers: shared hit=58 read=2122
                     ->  Hash Join  (cost=1.40..3635.40 rows=8000 width=30) (actual time=0.037..58.232 rows=8056 loops=1)
                           Hash Cond: (supplier.s_nationkey = n1.n_nationkey)
                           Buffers: shared hit=58 read=2122
                           ->  Seq Scan on supplier  (cost=0.00..3179.00 rows=100000 width=8) (actual time=0.004..43.363 rows=100000 loops=1)
                                 Buffers: shared hit=57 read=2122
                           ->  Hash  (cost=1.38..1.38 rows=2 width=30) (actual time=0.019..0.019 rows=2 loops=1)
                                 Buckets: 1024  Batches: 1  Memory Usage: 9kB
                                 Buffers: shared hit=1
                                 ->  Seq Scan on nation n1  (cost=0.00..1.38 rows=2 width=30) (actual time=0.008..0.013 rows=2 loops=1)
                                       Filter: ((n_name = 'GERMANY'::bpchar) OR (n_name = 'ARGENTINA'::bpchar))
                                       Rows Removed by Filter: 23
                                       Buffers: shared hit=1
 Planning time: 5.628 ms
 Execution time: 21883.994 ms
(54 rows)

COMMIT;
COMMIT