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 = 'GERMANY') or (n1.n_name = 'GERMANY' 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=2365112.36..2367015.00 rows=58543 width=64) (actual time=73407.058..73438.396 rows=4 loops=1) Buffers: shared hit=689784 read=746263 dirtied=1068 written=39422 -> Sort (cost=2365112.36..2365258.71 rows=58543 width=64) (actual time=73396.247..73406.166 rows=58694 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: 9790kB Buffers: shared hit=689784 read=746263 dirtied=1068 written=39422 -> Hash Join (cost=898041.08..2360476.57 rows=58543 width=64) (actual time=34550.587..73136.349 rows=58694 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (n1.n_nationkey = supplier.s_nationkey)) Buffers: shared hit=689776 read=746263 dirtied=1068 written=39422 -> Hash Join (cost=893362.08..2325615.26 rows=1465208 width=72) (actual time=34474.443..69932.454 rows=1467420 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=687594 read=746263 dirtied=1068 written=39422 -> Bitmap Heap Scan on lineitem (cost=387334.92..1736199.40 rows=18329765 width=20) (actual time=13087.725..27617.890 rows=18247062 loops=1) Recheck Cond: ((l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Buffers: shared hit=414501 read=705628 dirtied=1068 written=39422 -> Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx (cost=0.00..382752.48 rows=18329765 width=0) (actual time=12442.371..12442.371 rows=18374583 loops=1) Index Cond: ((l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Buffers: shared read=49815 -> Hash (cost=490919.26..490919.26 rows=1208632 width=60) (actual time=21385.970..21385.970 rows=1205631 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 108319kB Buffers: shared hit=273093 read=40635 -> Hash Join (cost=15638.06..490919.26 rows=1208632 width=60) (actual time=774.220..19757.126 rows=1205631 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=273093 read=40635 -> Seq Scan on orders (cost=0.00..406494.91 rows=15119991 width=8) (actual time=0.018..3811.373 rows=15015000 loops=1) Buffers: shared hit=249269 read=6026 -> Hash (cost=14139.26..14139.26 rows=119904 width=60) (actual time=774.039..774.039 rows=120218 loops=1) Buckets: 16384 Batches: 1 Memory Usage: 10801kB Buffers: shared hit=23824 read=34609 -> Nested Loop (cost=905.09..14139.26 rows=119904 width=60) (actual time=18.883..708.464 rows=120218 loops=1) Buffers: shared hit=23824 read=34609 -> Nested Loop (cost=0.00..28.00 rows=2 width=60) (actual time=0.148..0.364 rows=2 loops=1) Join Filter: (((n1.n_name = 'CHINA'::bpchar) AND (n2.n_name = 'GERMANY'::bpchar)) OR ((n1.n_name = 'GERMANY'::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=0.021..0.053 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=0.007..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=20.015..340.254 rows=60109 loops=2) Recheck Cond: (c_nationkey = n2.n_nationkey) Buffers: shared hit=23821 read=34609 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=13.271..13.271 rows=60109 loops=2) Index Cond: (c_nationkey = n2.n_nationkey) Buffers: shared hit=1 read=334 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=74.422..74.422 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..48.738 rows=100000 loops=1) Buffers: shared hit=2179 Total runtime: 73470.831 ms (53 rows) COMMIT; COMMIT