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 = 'UNITED STATES' and n2.n_name = 'ROMANIA') or (n1.n_name = 'ROMANIA' and n2.n_name = 'UNITED STATES') ) 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 ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1978741.01..1978748.68 rows=3067 width=64) (actual time=27202.924..27202.924 rows=4 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: 25kB Buffers: shared hit=5108127 read=431804 dirtied=1 written=7993 -> HashAggregate (cost=1978517.39..1978563.39 rows=3067 width=64) (actual time=27202.838..27202.845 rows=4 loops=1) Group Key: n1.n_name, n2.n_name, date_part('year'::text, (lineitem.l_shipdate)::timestamp without time zone) Buffers: shared hit=5108119 read=431804 dirtied=1 written=7993 -> Hash Join (cost=62340.37..1977603.00 rows=60959 width=64) (actual time=777.664..27111.387 rows=59117 loops=1) Hash Cond: (lineitem.l_suppkey = supplier.s_suppkey) Join Filter: (((n1.n_name = 'UNITED STATES'::bpchar) AND (n2.n_name = 'ROMANIA'::bpchar)) OR ((n1.n_name = 'ROMANIA'::bpchar) AND (n2.n_name = 'UNITED STATES'::bpchar))) Rows Removed by Join Filter: 58279 Buffers: shared hit=5108119 read=431804 dirtied=1 written=7993 -> Nested Loop (cost=58604.97..1965726.01 rows=1464831 width=42) (actual time=729.034..25979.921 rows=1464718 loops=1) Buffers: shared hit=5105936 read=431804 dirtied=1 written=7993 -> Hash Join (cost=58604.40..532478.49 rows=1205994 width=30) (actual time=728.886..14672.863 rows=1201745 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=230140 read=59673 dirtied=1 written=765 -> Seq Scan on orders (cost=0.00..405283.20 rows=15074920 width=8) (actual time=0.009..4015.676 rows=15015000 loops=1) Buffers: shared hit=194981 read=59553 dirtied=1 written=765 -> Hash (cost=57104.40..57104.40 rows=120000 width=30) (actual time=728.250..728.250 rows=120054 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 8293kB Buffers: shared hit=35159 read=120 -> Hash Join (cost=1.40..57104.40 rows=120000 width=30) (actual time=0.068..685.533 rows=120054 loops=1) Hash Cond: (customer.c_nationkey = n2.n_nationkey) Buffers: shared hit=35159 read=120 -> Seq Scan on customer (cost=0.00..50278.00 rows=1500000 width=8) (actual time=0.013..439.378 rows=1500000 loops=1) Buffers: shared hit=35158 read=120 -> Hash (cost=1.38..1.38 rows=2 width=30) (actual time=0.024..0.024 rows=2 loops=1) Buckets: 1024 Batches: 1 Memory Usage: 9kB Buffers: shared hit=1 -> Seq Scan on nation n2 (cost=0.00..1.38 rows=2 width=30) (actual time=0.018..0.019 rows=2 loops=1) Filter: ((n_name = 'ROMANIA'::bpchar) OR (n_name = 'UNITED STATES'::bpchar)) Rows Removed by Filter: 23 Buffers: shared hit=1 -> Index Scan using lineitem_l_orderkey_l_linenumber_l_shipdate_idx on lineitem (cost=0.56..1.15 rows=4 width=20) (actual time=0.008..0.009 rows=1 loops=1201745) Index Cond: ((l_orderkey = orders.o_orderkey) AND (l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Buffers: shared hit=4875796 read=372131 written=7228 -> Hash (cost=3635.40..3635.40 rows=8000 width=30) (actual time=48.172..48.172 rows=8033 loops=1) Buckets: 8192 Batches: 1 Memory Usage: 551kB Buffers: shared hit=2180 -> Hash Join (cost=1.40..3635.40 rows=8000 width=30) (actual time=0.044..45.960 rows=8033 loops=1) Hash Cond: (supplier.s_nationkey = n1.n_nationkey) Buffers: shared hit=2180 -> Seq Scan on supplier (cost=0.00..3179.00 rows=100000 width=8) (actual time=0.009..29.661 rows=100000 loops=1) Buffers: shared hit=2179 -> Hash (cost=1.38..1.38 rows=2 width=30) (actual time=0.021..0.021 rows=2 loops=1) Buckets: 1024 Batches: 1 Memory Usage: 9kB Buffers: shared hit=1 -> Seq Scan on nation n1 (cost=0.00..1.38 rows=2 width=30) (actual time=0.015..0.018 rows=2 loops=1) Filter: ((n_name = 'UNITED STATES'::bpchar) OR (n_name = 'ROMANIA'::bpchar)) Rows Removed by Filter: 23 Buffers: shared hit=1 Planning time: 6.169 ms Execution time: 27203.467 ms (54 rows) COMMIT; COMMIT