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 = 'EGYPT' and n2.n_name = 'CHINA') or (n1.n_name = 'CHINA' and n2.n_name = 'EGYPT') ) 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 --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- GroupAggregate (cost=2362711.84..2364618.55 rows=58668 width=64) (actual time=82553.746..82579.677 rows=4 loops=1) Buffers: shared hit=632581 read=799607 written=36022 -> Sort (cost=2362711.84..2362858.51 rows=58668 width=64) (actual time=82544.448..82549.528 rows=58302 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: 9735kB Buffers: shared hit=632581 read=799607 written=36022 -> Hash Join (cost=897990.49..2358065.25 rows=58668 width=64) (actual time=40012.247..82278.669 rows=58302 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (n1.n_nationkey = supplier.s_nationkey)) Buffers: shared hit=632573 read=799607 written=36022 -> Hash Join (cost=893311.49..2323140.43 rows=1468290 width=72) (actual time=39944.621..79105.324 rows=1463904 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=630391 read=799607 written=36022 -> Bitmap Heap Scan on lineitem (cost=388746.13..1735010.96 rows=18368322 width=20) (actual time=14895.804..32910.259 rows=18247443 loops=1) Recheck Cond: ((l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Buffers: shared hit=324371 read=792589 written=36022 -> Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx (cost=0.00..384154.05 rows=18368322 width=0) (actual time=14091.652..14091.652 rows=18320255 loops=1) Index Cond: ((l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Buffers: shared read=49815 written=3 -> Hash (cost=489502.50..489502.50 rows=1205029 width=60) (actual time=25047.997..25047.997 rows=1203298 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 108109kB Buffers: shared hit=306020 read=7018 -> Hash Join (cost=15638.06..489502.50 rows=1205029 width=60) (actual time=475.428..23239.030 rows=1203298 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=306020 read=7018 -> Seq Scan on orders (cost=0.00..405283.20 rows=15074920 width=8) (actual time=0.020..4080.573 rows=15015000 loops=1) Buffers: shared hit=248759 read=5775 -> Hash (cost=14139.26..14139.26 rows=119904 width=60) (actual time=475.267..475.267 rows=120034 loops=1) Buckets: 16384 Batches: 1 Memory Usage: 10785kB Buffers: shared hit=57261 read=1243 -> Nested Loop (cost=905.09..14139.26 rows=119904 width=60) (actual time=19.094..413.962 rows=120034 loops=1) Buffers: shared hit=57261 read=1243 -> Nested Loop (cost=0.00..28.00 rows=2 width=60) (actual time=0.139..0.450 rows=2 loops=1) Join Filter: (((n1.n_name = 'EGYPT'::bpchar) AND (n2.n_name = 'CHINA'::bpchar)) OR ((n1.n_name = 'CHINA'::bpchar) AND (n2.n_name = 'EGYPT'::bpchar))) Rows Removed by Join Filter: 623 Buffers: shared hit=3 -> Index Scan using pk_nation on nation n1 (cost=0.00..12.63 rows=25 width=30) (actual time=0.028..0.049 rows=25 loops=1) Buffers: shared hit=2 -> Materialize (cost=0.00..1.38 rows=25 width=30) (actual time=0.001..0.004 rows=25 loops=25) Buffers: shared hit=1 -> Seq Scan on nation n2 (cost=0.00..1.25 rows=25 width=30) (actual time=0.008..0.011 rows=25 loops=1) Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=905.09..6455.63 rows=60000 width=8) (actual time=24.515..190.679 rows=60017 loops=2) Recheck Cond: (c_nationkey = n2.n_nationkey) Buffers: shared hit=57258 read=1243 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=16.605..16.605 rows=60017 loops=2) Index Cond: (c_nationkey = n2.n_nationkey) Buffers: shared hit=3 read=332 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=67.282..67.282 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..39.281 rows=100000 loops=1) Buffers: shared hit=2179 Total runtime: 82616.229 ms (53 rows) COMMIT; COMMIT