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 = 'CHINA' and n2.n_name = 'ROMANIA') or (n1.n_name = 'ROMANIA' and n2.n_name = 'CHINA') ) 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=2351147.99..2353041.77 rows=58270 width=64) (actual time=57547.109..57569.462 rows=4 loops=1) Buffers: shared hit=338032 read=1088782 -> Sort (cost=2351147.99..2351293.67 rows=58270 width=64) (actual time=57539.792..57543.314 rows=58585 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: 9775kB Buffers: shared hit=338032 read=1088782 -> Hash Join (cost=893783.55..2346535.79 rows=58270 width=64) (actual time=21149.636..57308.068 rows=58585 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (n1.n_nationkey = supplier.s_nationkey)) Buffers: shared hit=338024 read=1088782 -> Hash Join (cost=889104.55..2311847.62 rows=1456756 width=72) (actual time=21085.988..53846.737 rows=1465907 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=335842 read=1088782 -> Bitmap Heap Scan on lineitem (cost=386483.11..1726318.51 rows=18224027 width=20) (actual time=10307.829..24136.746 rows=18248249 loops=1) Recheck Cond: ((l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Buffers: shared hit=24115 read=1088596 -> Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx (cost=0.00..381927.10 rows=18224027 width=0) (actual time=9722.526..9722.526 rows=18248249 loops=1) Index Cond: ((l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Buffers: shared read=49815 -> Hash (cost=487618.47..487618.47 rows=1200238 width=60) (actual time=10777.022..10777.022 rows=1202913 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 108075kB Buffers: shared hit=311727 read=186 -> Hash Join (cost=15638.06..487618.47 rows=1200238 width=60) (actual time=305.072..10292.481 rows=1202913 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=311727 read=186 -> Seq Scan on orders (cost=0.00..403671.84 rows=15014984 width=8) (actual time=0.021..3282.348 rows=15015000 loops=1) Buffers: shared hit=253502 read=20 -> Hash (cost=14139.26..14139.26 rows=119904 width=60) (actual time=304.835..304.835 rows=120113 loops=1) Buckets: 16384 Batches: 1 Memory Usage: 10792kB Buffers: shared hit=58225 read=166 -> Nested Loop (cost=905.09..14139.26 rows=119904 width=60) (actual time=16.015..266.250 rows=120113 loops=1) Buffers: shared hit=58225 read=166 -> Nested Loop (cost=0.00..28.00 rows=2 width=60) (actual time=0.220..0.336 rows=2 loops=1) Join Filter: (((n1.n_name = 'CHINA'::bpchar) AND (n2.n_name = 'ROMANIA'::bpchar)) OR ((n1.n_name = 'ROMANIA'::bpchar) AND (n2.n_name = 'CHINA'::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=0.020..0.037 rows=25 loops=1) Buffers: shared hit=2 -> Materialize (cost=0.00..1.38 rows=25 width=30) (actual time=0.001..0.003 rows=25 loops=25) Buffers: shared hit=1 -> Seq Scan on nation n2 (cost=0.00..1.25 rows=25 width=30) (actual time=0.006..0.006 rows=25 loops=1) Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=905.09..6455.63 rows=60000 width=8) (actual time=15.838..122.591 rows=60056 loops=2) Recheck Cond: (c_nationkey = n2.n_nationkey) Buffers: shared hit=58222 read=166 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=10.181..10.181 rows=60056 loops=2) Index Cond: (c_nationkey = n2.n_nationkey) Buffers: shared hit=172 read=164 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=63.468..63.468 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=0.012..34.917 rows=100000 loops=1) Buffers: shared hit=2179 Total runtime: 57590.219 ms (53 rows) COMMIT; COMMIT