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 = 'MOROCCO' and n2.n_name = 'JAPAN')
				or (n1.n_name = 'JAPAN' and n2.n_name = 'MOROCCO')
			)
			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=1978761.10..1978768.79 rows=3074 width=64) (actual time=19349.524..19349.525 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=5064768 read=453982 dirtied=253 written=1527
   ->  HashAggregate  (cost=1978536.92..1978583.03 rows=3074 width=64) (actual time=19349.440..19349.447 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=5064760 read=453982 dirtied=253 written=1527
         ->  Hash Join  (cost=62340.37..1977620.55 rows=61091 width=64) (actual time=906.033..19265.292 rows=57987 loops=1)
               Hash Cond: (lineitem.l_suppkey = supplier.s_suppkey)
               Join Filter: (((n1.n_name = 'MOROCCO'::bpchar) AND (n2.n_name = 'JAPAN'::bpchar)) OR ((n1.n_name = 'JAPAN'::bpchar) AND (n2.n_name = 'MOROCCO'::bpchar)))
               Rows Removed by Join Filter: 58206
               Buffers: shared hit=5064760 read=453982 dirtied=253 written=1527
               ->  Nested Loop  (cost=58604.97..1965726.01 rows=1467980 width=42) (actual time=849.964..18658.715 rows=1454236 loops=1)
                     Buffers: shared hit=5062577 read=453982 dirtied=253 written=1527
                     ->  Hash Join  (cost=58604.40..532478.49 rows=1205994 width=30) (actual time=849.836..9050.082 rows=1197096 loops=1)
                           Hash Cond: (orders.o_custkey = customer.c_custkey)
                           Buffers: shared hit=199937 read=89876 dirtied=253 written=221
                           ->  Seq Scan on orders  (cost=0.00..405283.20 rows=15074920 width=8) (actual time=0.006..3492.058 rows=15015000 loops=1)
                                 Buffers: shared hit=199934 read=54600 dirtied=253 written=221
                           ->  Hash  (cost=57104.40..57104.40 rows=120000 width=30) (actual time=849.191..849.191 rows=119591 loops=1)
                                 Buckets: 131072  Batches: 1  Memory Usage: 8265kB
                                 Buffers: shared hit=3 read=35276
                                 ->  Hash Join  (cost=1.40..57104.40 rows=120000 width=30) (actual time=0.054..804.872 rows=119591 loops=1)
                                       Hash Cond: (customer.c_nationkey = n2.n_nationkey)
                                       Buffers: shared hit=3 read=35276
                                       ->  Seq Scan on customer  (cost=0.00..50278.00 rows=1500000 width=8) (actual time=0.009..577.714 rows=1500000 loops=1)
                                             Buffers: shared hit=2 read=35276
                                       ->  Hash  (cost=1.38..1.38 rows=2 width=30) (actual time=0.033..0.033 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=0.019..0.022 rows=2 loops=1)
                                                   Filter: ((n_name = 'JAPAN'::bpchar) OR (n_name = 'MOROCCO'::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..1.15 rows=4 width=20) (actual time=0.007..0.007 rows=1 loops=1197096)
                           Index Cond: ((l_orderkey = orders.o_orderkey) AND (l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date))
                           Buffers: shared hit=4862640 read=364106 written=1306
               ->  Hash  (cost=3635.40..3635.40 rows=8000 width=30) (actual time=55.934..55.934 rows=7999 loops=1)
                     Buckets: 8192  Batches: 1  Memory Usage: 549kB
                     Buffers: shared hit=2180
                     ->  Hash Join  (cost=1.40..3635.40 rows=8000 width=30) (actual time=0.052..53.686 rows=7999 loops=1)
                           Hash Cond: (supplier.s_nationkey = n1.n_nationkey)
                           Buffers: shared hit=2180
                           ->  Seq Scan on supplier  (cost=0.00..3179.00 rows=100000 width=8) (actual time=0.015..37.190 rows=100000 loops=1)
                                 Buffers: shared hit=2179
                           ->  Hash  (cost=1.38..1.38 rows=2 width=30) (actual time=0.022..0.022 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=0.013..0.016 rows=2 loops=1)
                                       Filter: ((n_name = 'MOROCCO'::bpchar) OR (n_name = 'JAPAN'::bpchar))
                                       Rows Removed by Filter: 23
                                       Buffers: shared hit=1
 Planning time: 5.585 ms
 Execution time: 19350.054 ms
(54 rows)

COMMIT;
COMMIT