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 = 'EUROPE' and o_orderdate >= date '1993-01-01' and o_orderdate < date '1993-01-01' + interval '1 year' group by n_name order by revenue desc; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2428983.96..2428984.02 rows=25 width=34) (actual time=86689.334..86689.335 rows=5 loops=1) Sort Key: (sum((lineitem.l_extendedprice * (1::double precision - lineitem.l_discount)))) Sort Method: quicksort Memory: 25kB Buffers: shared hit=738240 read=740283 written=13 -> HashAggregate (cost=2428983.13..2428983.38 rows=25 width=34) (actual time=86689.266..86689.270 rows=5 loops=1) Buffers: shared hit=738237 read=740283 written=13 -> Hash Join (cost=399597.28..2428251.50 rows=73163 width=34) (actual time=15370.355..86484.170 rows=72814 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (customer.c_nationkey = supplier.s_nationkey)) Buffers: shared hit=738237 read=740283 written=13 -> Hash Join (cost=394918.28..2386259.95 rows=1829046 width=46) (actual time=15246.277..82515.563 rows=1829185 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=736055 read=740283 written=13 -> Seq Scan on lineitem (cost=0.00..1671922.81 rows=60225681 width=16) (actual time=0.032..22745.109 rows=60045303 loops=1) Buffers: shared hit=356180 read=713486 written=4 -> Hash (cost=389201.18..389201.18 rows=457368 width=38) (actual time=15245.583..15245.583 rows=457443 loops=1) Buckets: 65536 Batches: 1 Memory Usage: 32164kB Buffers: shared hit=379875 read=26797 written=9 -> Hash Join (cost=87468.23..389201.18 rows=457368 width=38) (actual time=3692.333..14850.374 rows=457443 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=379875 read=26797 written=9 -> Bitmap Heap Scan on orders (cost=48426.02..337009.63 rows=2286841 width=8) (actual time=1764.919..6282.200 rows=2279058 loops=1) Recheck Cond: ((o_orderdate >= '1993-01-01'::date) AND (o_orderdate < '1994-01-01 00:00:00'::timestamp without time zone)) Buffers: shared hit=252602 read=7892 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..47854.31 rows=2286841 width=0) (actual time=1645.009..1645.009 rows=2285733 loops=1) Index Cond: ((o_orderdate >= '1993-01-01'::date) AND (o_orderdate < '1994-01-01 00:00:00'::timestamp without time zone)) Buffers: shared read=6225 -> Hash (cost=35292.22..35292.22 rows=300000 width=38) (actual time=1926.730..1926.730 rows=300963 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 21162kB Buffers: shared hit=127273 read=18905 written=9 -> Nested Loop (cost=905.09..35292.22 rows=300000 width=38) (actual time=43.402..1694.728 rows=300963 loops=1) Buffers: shared hit=127273 read=18905 written=9 -> Nested Loop (cost=0.00..14.07 rows=5 width=30) (actual time=0.077..0.147 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..0.045 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..0.033 rows=1 loops=1) Filter: (r_name = 'EUROPE'::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=35.185..310.592 rows=60193 loops=5) Recheck Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=127270 read=18905 written=9 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=24.427..24.427 rows=60193 loops=5) Index Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=6 read=833 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=123.637..123.637 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=0.009..80.064 rows=100000 loops=1) Buffers: shared hit=2179 Total runtime: 86706.775 ms (55 rows) COMMIT; COMMIT