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 = 'CANADA' and n2.n_name = 'MOZAMBIQUE') or (n1.n_name = 'MOZAMBIQUE' and n2.n_name = 'CANADA') ) 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=2379763.07..2381684.95 rows=59135 width=64) (actual time=79906.326..79933.684 rows=4 loops=1) Buffers: shared hit=778638 read=663990 written=107 -> Sort (cost=2379763.07..2379910.90 rows=59135 width=64) (actual time=79896.411..79901.728 rows=57956 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: 9687kB Buffers: shared hit=778638 read=663990 written=107 -> Hash Join (cost=903380.65..2375076.11 rows=59135 width=64) (actual time=41344.841..79591.847 rows=57956 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (n1.n_nationkey = supplier.s_nationkey)) Buffers: shared hit=778630 read=663990 written=107 -> Hash Join (cost=898701.65..2339910.56 rows=1479976 width=72) (actual time=41255.016..76441.938 rows=1449699 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=776448 read=663990 written=107 -> Bitmap Heap Scan on lineitem (cost=390244.61..1747224.33 rows=18514515 width=20) (actual time=14245.216..29329.136 rows=18227973 loops=1) Recheck Cond: ((l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Buffers: shared hit=546034 read=579421 written=101 -> Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx (cost=0.00..385615.98 rows=18514515 width=0) (actual time=13499.751..13499.751 rows=18466690 loops=1) Index Cond: ((l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Buffers: shared read=49815 -> Hash (cost=493274.29..493274.29 rows=1214620 width=60) (actual time=27008.845..27008.845 rows=1193896 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 107265kB Buffers: shared hit=230414 read=84569 written=6 -> Hash Join (cost=15638.06..493274.29 rows=1214620 width=60) (actual time=725.979..26308.478 rows=1193896 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=230414 read=84569 written=6 -> Seq Scan on orders (cost=0.00..408509.11 rows=15194911 width=8) (actual time=0.016..4158.246 rows=15000000 loops=1) Buffers: shared hit=206577 read=49983 written=6 -> Hash (cost=14139.26..14139.26 rows=119904 width=60) (actual time=725.817..725.817 rows=119645 loops=1) Buckets: 16384 Batches: 1 Memory Usage: 10750kB Buffers: shared hit=23837 read=34586 -> Nested Loop (cost=905.09..14139.26 rows=119904 width=60) (actual time=18.768..665.694 rows=119645 loops=1) Buffers: shared hit=23837 read=34586 -> Nested Loop (cost=0.00..28.00 rows=2 width=60) (actual time=0.109..0.344 rows=2 loops=1) Join Filter: (((n1.n_name = 'CANADA'::bpchar) AND (n2.n_name = 'MOZAMBIQUE'::bpchar)) OR ((n1.n_name = 'MOZAMBIQUE'::bpchar) AND (n2.n_name = 'CANADA'::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=0.021..0.041 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=0.005..0.010 rows=25 loops=1) Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=905.09..6455.63 rows=60000 width=8) (actual time=19.342..318.097 rows=59822 loops=2) Recheck Cond: (c_nationkey = n2.n_nationkey) Buffers: shared hit=23834 read=34586 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=12.665..12.665 rows=59822 loops=2) Index Cond: (c_nationkey = n2.n_nationkey) Buffers: shared hit=1 read=332 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=88.889..88.889 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=0.016..55.328 rows=100000 loops=1) Buffers: shared hit=2179 Total runtime: 79966.647 ms (53 rows) COMMIT; COMMIT