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 '1996-01-01' and o_orderdate < date '1996-01-01' + interval '1 year' group by n_name order by revenue desc; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2423862.42..2423862.48 rows=25 width=34) (actual time=84223.686..84223.687 rows=5 loops=1) Sort Key: (sum((lineitem.l_extendedprice * (1::double precision - lineitem.l_discount)))) Sort Method: quicksort Memory: 25kB Buffers: shared hit=840911 read=634756 dirtied=253 written=595 -> HashAggregate (cost=2423861.59..2423861.84 rows=25 width=34) (actual time=84223.617..84223.620 rows=5 loops=1) Buffers: shared hit=840908 read=634756 dirtied=253 written=595 -> Hash Join (cost=398655.90..2423133.47 rows=72812 width=34) (actual time=17249.719..84057.298 rows=73354 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (customer.c_nationkey = supplier.s_nationkey)) Buffers: shared hit=840908 read=634756 dirtied=253 written=595 -> Hash Join (cost=393976.90..2381320.57 rows=1820289 width=46) (actual time=17138.858..80137.764 rows=1824279 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=838726 read=634756 dirtied=253 written=595 -> Seq Scan on lineitem (cost=0.00..1668609.18 rows=60106318 width=16) (actual time=0.040..20189.783 rows=60045603 loops=1) Buffers: shared hit=715655 read=351891 -> Hash (cost=388287.21..388287.21 rows=455175 width=38) (actual time=17138.277..17138.277 rows=456297 loops=1) Buckets: 65536 Batches: 1 Memory Usage: 32084kB Buffers: shared hit=123071 read=282865 dirtied=253 written=595 -> Hash Join (cost=87287.82..388287.21 rows=455175 width=38) (actual time=3378.391..14731.468 rows=456297 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=123071 read=282865 dirtied=253 written=595 -> Bitmap Heap Scan on orders (cost=48245.60..336158.71 rows=2275874 width=8) (actual time=1639.874..6758.548 rows=2284056 loops=1) Recheck Cond: ((o_orderdate >= '1996-01-01'::date) AND (o_orderdate < '1997-01-01 00:00:00'::timestamp without time zone)) Buffers: shared hit=8204 read=251793 dirtied=253 written=163 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..47676.64 rows=2275874 width=0) (actual time=1490.608..1490.608 rows=2286330 loops=1) Index Cond: ((o_orderdate >= '1996-01-01'::date) AND (o_orderdate < '1997-01-01 00:00:00'::timestamp without time zone)) Buffers: shared hit=352 read=5887 -> Hash (cost=35292.22..35292.22 rows=300000 width=38) (actual time=1738.249..1738.249 rows=299436 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 21055kB Buffers: shared hit=114867 read=31072 written=432 -> Nested Loop (cost=905.09..35292.22 rows=300000 width=38) (actual time=34.201..1545.349 rows=299436 loops=1) Buffers: shared hit=114867 read=31072 written=432 -> Nested Loop (cost=0.00..14.07 rows=5 width=30) (actual time=0.081..0.181 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=0.022..0.063 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=0.029..0.030 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=29.548..285.120 rows=59887 loops=5) Recheck Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=114864 read=31072 written=432 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=20.966..20.966 rows=59887 loops=5) Index Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=7 read=827 written=4 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=110.641..110.641 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=0.010..64.475 rows=100000 loops=1) Buffers: shared hit=2179 Total runtime: 84241.862 ms (55 rows) COMMIT; COMMIT