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 = 'IRAN' and n2.n_name = 'CANADA') or (n1.n_name = 'CANADA' and n2.n_name = 'IRAN') ) 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=2352874.37..2354765.78 rows=58197 width=64) (actual time=99338.961..99364.467 rows=4 loops=1) Buffers: shared hit=923973 read=505552 dirtied=817 written=4182 -> Sort (cost=2352874.37..2353019.87 rows=58197 width=64) (actual time=99329.661..99334.216 rows=58548 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: 9770kB Buffers: shared hit=923973 read=505552 dirtied=817 written=4182 -> Hash Join (cost=893871.42..2348268.47 rows=58197 width=64) (actual time=47566.735..99026.641 rows=58548 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (n1.n_nationkey = supplier.s_nationkey)) Buffers: shared hit=923965 read=505552 dirtied=817 written=4182 -> Hash Join (cost=889192.42..2313618.22 rows=1454915 width=72) (actual time=47442.673..95562.625 rows=1446514 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=921783 read=505552 dirtied=817 written=4182 -> Bitmap Heap Scan on lineitem (cost=385599.03..1727221.95 rows=18200995 width=20) (actual time=16574.226..38763.914 rows=18248203 loops=1) Recheck Cond: ((l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Buffers: shared hit=645674 read=469164 dirtied=817 written=4182 -> Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx (cost=0.00..381048.78 rows=18200995 width=0) (actual time=15720.312..15720.312 rows=18284460 loops=1) Index Cond: ((l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Buffers: shared hit=2 read=49813 -> Hash (cost=488560.48..488560.48 rows=1202633 width=60) (actual time=30867.459..30867.459 rows=1194195 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 107291kB Buffers: shared hit=276109 read=36388 -> Hash Join (cost=15638.06..488560.48 rows=1202633 width=60) (actual time=1111.411..29507.904 rows=1194195 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=276109 read=36388 -> Seq Scan on orders (cost=0.00..404477.52 rows=15044952 width=8) (actual time=0.017..5315.952 rows=15015000 loops=1) Buffers: shared hit=237887 read=16141 -> Hash (cost=14139.26..14139.26 rows=119904 width=60) (actual time=1111.204..1111.204 rows=119950 loops=1) Buckets: 16384 Batches: 1 Memory Usage: 10777kB Buffers: shared hit=38222 read=20247 -> Nested Loop (cost=905.09..14139.26 rows=119904 width=60) (actual time=19.354..853.244 rows=119950 loops=1) Buffers: shared hit=38222 read=20247 -> Nested Loop (cost=0.00..28.00 rows=2 width=60) (actual time=0.103..0.428 rows=2 loops=1) Join Filter: (((n1.n_name = 'IRAN'::bpchar) AND (n2.n_name = 'CANADA'::bpchar)) OR ((n1.n_name = 'CANADA'::bpchar) AND (n2.n_name = 'IRAN'::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..0.045 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..0.007 rows=25 loops=1) Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=905.09..6455.63 rows=60000 width=8) (actual time=25.029..404.858 rows=59975 loops=2) Recheck Cond: (c_nationkey = n2.n_nationkey) Buffers: shared hit=38219 read=20247 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=17.093..17.093 rows=59975 loops=2) Index Cond: (c_nationkey = n2.n_nationkey) Buffers: shared hit=2 read=333 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=120.427..120.427 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=0.017..72.337 rows=100000 loops=1) Buffers: shared hit=2179 Total runtime: 99412.856 ms (53 rows) COMMIT; COMMIT