BEGIN;
BEGIN
EXPLAIN (ANALYZE, BUFFERS)
select
	n_name,
	sum(l_extendedprice * (1 - l_discount)) as revenue
from
	customer,
	orders,
	lineitem,
	supplier,
	nation,
	region
where
	c_custkey = o_custkey
	and l_orderkey = o_orderkey
	and l_suppkey = s_suppkey
	and c_nationkey = s_nationkey
	and s_nationkey = n_nationkey
	and n_regionkey = r_regionkey
	and r_name = 'AMERICA'
	and o_orderdate >= date '1997-01-01'
	and o_orderdate < date '1997-01-01' + interval '1 year'
group by
	n_name
order by
	revenue desc;
                                                                                              QUERY PLAN                                                                                               
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Sort  (cost=2427732.07..2427732.14 rows=25 width=34) (actual time=86153.569..86153.569 rows=5 loops=1)
   Sort Key: (sum((lineitem.l_extendedprice * (1::double precision - lineitem.l_discount))))
   Sort Method: quicksort  Memory: 25kB
   Buffers: shared hit=1011813 read=465150 written=5
   ->  HashAggregate  (cost=2427731.24..2427731.49 rows=25 width=34) (actual time=86153.422..86153.425 rows=5 loops=1)
         Buffers: shared hit=1011810 read=465150 written=5
         ->  Hash Join  (cost=399965.93..2426995.31 rows=73593 width=34) (actual time=14909.000..85902.358 rows=72767 loops=1)
               Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (customer.c_nationkey = supplier.s_nationkey))
               Buffers: shared hit=1011810 read=465150 written=5
               ->  Hash Join  (cost=395286.93..2384784.54 rows=1839792 width=46) (actual time=14759.541..81073.528 rows=1821138 loops=1)
                     Hash Cond: (lineitem.l_orderkey = orders.o_orderkey)
                     Buffers: shared hit=1009628 read=465150 written=5
                     ->  Seq Scan on lineitem  (cost=0.00..1670269.12 rows=60166112 width=16) (actual time=0.035..23341.693 rows=60045379 loops=1)
                           Buffers: shared hit=616034 read=452574 written=5
                     ->  Hash  (cost=389536.27..389536.27 rows=460053 width=38) (actual time=14758.729..14758.729 rows=455310 loops=1)
                           Buckets: 65536  Batches: 1  Memory Usage: 32014kB
                           Buffers: shared hit=393594 read=12576
                           ->  Hash Join  (cost=87777.81..389536.27 rows=460053 width=38) (actual time=3497.153..14403.917 rows=455310 loops=1)
                                 Hash Cond: (orders.o_custkey = customer.c_custkey)
                                 Buffers: shared hit=393594 read=12576
                                 ->  Bitmap Heap Scan on orders  (cost=48735.59..337267.54 rows=2300263 width=8) (actual time=1952.802..5701.297 rows=2277833 loops=1)
                                       Recheck Cond: ((o_orderdate >= '1997-01-01'::date) AND (o_orderdate < '1998-01-01 00:00:00'::timestamp without time zone))
                                       Buffers: shared hit=253434 read=6797
                                       ->  Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx  (cost=0.00..48160.53 rows=2300263 width=0) (actual time=1810.807..1810.807 rows=2282427 loops=1)
                                             Index Cond: ((o_orderdate >= '1997-01-01'::date) AND (o_orderdate < '1998-01-01 00:00:00'::timestamp without time zone))
                                             Buffers: shared read=6221
                                 ->  Hash  (cost=35292.22..35292.22 rows=300000 width=38) (actual time=1543.280..1543.280 rows=299436 loops=1)
                                       Buckets: 32768  Batches: 1  Memory Usage: 21055kB
                                       Buffers: shared hit=140160 read=5779
                                       ->  Nested Loop  (cost=905.09..35292.22 rows=300000 width=38) (actual time=34.414..1327.376 rows=299436 loops=1)
                                             Buffers: shared hit=140160 read=5779
                                             ->  Nested Loop  (cost=0.00..14.07 rows=5 width=30) (actual time=0.059..0.165 rows=5 loops=1)
                                                   Join Filter: (nation.n_regionkey = region.r_regionkey)
                                                   Rows Removed by Join Filter: 20
                                                   Buffers: shared hit=3
                                                   ->  Index Scan using pk_nation on nation  (cost=0.00..12.63 rows=25 width=34) (actual time=0.012..0.050 rows=25 loops=1)
                                                         Buffers: shared hit=2
                                                   ->  Materialize  (cost=0.00..1.07 rows=1 width=4) (actual time=0.002..0.003 rows=1 loops=25)
                                                         Buffers: shared hit=1
                                                         ->  Seq Scan on region  (cost=0.00..1.06 rows=1 width=4) (actual time=0.028..0.029 rows=1 loops=1)
                                                               Filter: (r_name = 'AMERICA'::bpchar)
                                                               Rows Removed by Filter: 4
                                                               Buffers: shared hit=1
                                             ->  Bitmap Heap Scan on customer  (cost=905.09..6455.63 rows=60000 width=8) (actual time=33.155..239.601 rows=59887 loops=5)
                                                   Recheck Cond: (c_nationkey = nation.n_nationkey)
                                                   Buffers: shared hit=140157 read=5779
                                                   ->  Bitmap Index Scan on customer_c_nationkey_c_custkey_idx  (cost=0.00..890.09 rows=60000 width=0) (actual time=22.913..22.913 rows=59887 loops=5)
                                                         Index Cond: (c_nationkey = nation.n_nationkey)
                                                         Buffers: shared hit=7 read=827
               ->  Hash  (cost=3179.00..3179.00 rows=100000 width=8) (actual time=148.648..148.648 rows=100000 loops=1)
                     Buckets: 16384  Batches: 1  Memory Usage: 3907kB
                     Buffers: shared hit=2179
                     ->  Seq Scan on supplier  (cost=0.00..3179.00 rows=100000 width=8) (actual time=0.017..93.629 rows=100000 loops=1)
                           Buffers: shared hit=2179
 Total runtime: 86173.164 ms
(55 rows)

COMMIT;
COMMIT