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 '1995-01-01'
	and o_orderdate < date '1995-01-01' + interval '1 year'
group by
	n_name
order by
	revenue desc;
                                                                                              QUERY PLAN                                                                                               
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Sort  (cost=2426778.28..2426778.34 rows=25 width=34) (actual time=157240.290..157240.328 rows=5 loops=1)
   Sort Key: (sum((lineitem.l_extendedprice * (1::double precision - lineitem.l_discount))))
   Sort Method: quicksort  Memory: 25kB
   Buffers: shared hit=988268 read=488693
   ->  HashAggregate  (cost=2426777.45..2426777.70 rows=25 width=34) (actual time=157240.154..157240.166 rows=5 loops=1)
         Buffers: shared hit=988265 read=488693
         ->  Hash Join  (cost=399363.76..2426046.01 rows=73144 width=34) (actual time=30396.886..156902.965 rows=72818 loops=1)
               Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (customer.c_nationkey = supplier.s_nationkey))
               Buffers: shared hit=988265 read=488693
               ->  Hash Join  (cost=394684.76..2384057.27 rows=1828915 width=46) (actual time=30198.163..151461.467 rows=1818187 loops=1)
                     Hash Cond: (lineitem.l_orderkey = orders.o_orderkey)
                     Buffers: shared hit=986083 read=488693
                     ->  Seq Scan on lineitem  (cost=0.00..1670258.24 rows=60165024 width=16) (actual time=0.056..66364.041 rows=60045379 loops=1)
                           Buffers: shared hit=607376 read=461232
                     ->  Hash  (cost=388968.00..388968.00 rows=457341 width=38) (actual time=30192.111..30192.111 rows=454919 loops=1)
                           Buckets: 65536  Batches: 1  Memory Usage: 31987kB
                           Buffers: shared hit=378707 read=27461
                           ->  Hash Join  (cost=87490.85..388968.00 rows=457341 width=38) (actual time=8118.878..29700.235 rows=454919 loops=1)
                                 Hash Cond: (orders.o_custkey = customer.c_custkey)
                                 Buffers: shared hit=378707 read=27461
                                 ->  Bitmap Heap Scan on orders  (cost=48448.63..336777.22 rows=2286706 width=8) (actual time=2745.615..15733.794 rows=2277879 loops=1)
                                       Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate < '1996-01-01 00:00:00'::timestamp without time zone))
                                       Buffers: shared hit=233631 read=26598
                                       ->  Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx  (cost=0.00..47876.96 rows=2286706 width=0) (actual time=2590.635..2590.635 rows=2282432 loops=1)
                                             Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate < '1996-01-01 00:00:00'::timestamp without time zone))
                                             Buffers: shared read=6221
                                 ->  Hash  (cost=35292.22..35292.22 rows=300000 width=38) (actual time=5373.001..5373.001 rows=299436 loops=1)
                                       Buckets: 32768  Batches: 1  Memory Usage: 21055kB
                                       Buffers: shared hit=145076 read=863
                                       ->  Nested Loop  (cost=905.09..35292.22 rows=300000 width=38) (actual time=53.367..5114.824 rows=299436 loops=1)
                                             Buffers: shared hit=145076 read=863
                                             ->  Nested Loop  (cost=0.00..14.07 rows=5 width=30) (actual time=0.070..0.186 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=0.015..0.061 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=0.032..0.034 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=50.404..994.725 rows=59887 loops=5)
                                                   Recheck Cond: (c_nationkey = nation.n_nationkey)
                                                   Buffers: shared hit=145073 read=863
                                                   ->  Bitmap Index Scan on customer_c_nationkey_c_custkey_idx  (cost=0.00..890.09 rows=60000 width=0) (actual time=38.765..38.765 rows=59887 loops=5)
                                                         Index Cond: (c_nationkey = nation.n_nationkey)
                                                         Buffers: shared hit=9 read=825
               ->  Hash  (cost=3179.00..3179.00 rows=100000 width=8) (actual time=194.570..194.570 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=0.020..144.307 rows=100000 loops=1)
                           Buffers: shared hit=2179
 Total runtime: 157265.571 ms
(55 rows)

COMMIT;
COMMIT