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 = 'PERU' and n2.n_name = 'ROMANIA') or (n1.n_name = 'ROMANIA' and n2.n_name = 'PERU') ) 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=2147828.24..2147835.93 rows=3076 width=64) (actual time=23666.270..23666.271 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=5681330 read=665442 dirtied=144 written=10433 -> HashAggregate (cost=2147603.90..2147650.04 rows=3076 width=64) (actual time=23666.202..23666.208 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=5681322 read=665442 dirtied=144 written=10433 -> Hash Join (cost=62340.37..2146683.24 rows=61377 width=64) (actual time=925.558..23572.532 rows=58453 loops=1) Hash Cond: (lineitem.l_suppkey = supplier.s_suppkey) Join Filter: (((n1.n_name = 'PERU'::bpchar) AND (n2.n_name = 'ROMANIA'::bpchar)) OR ((n1.n_name = 'ROMANIA'::bpchar) AND (n2.n_name = 'PERU'::bpchar))) Rows Removed by Join Filter: 58025 Buffers: shared hit=5681322 read=665442 dirtied=144 written=10433 -> Nested Loop (cost=58604.97..2134741.46 rows=1477263 width=42) (actual time=877.753..22922.154 rows=1453489 loops=1) Buffers: shared hit=5679139 read=665442 dirtied=144 written=10433 -> Hash Join (cost=58604.40..535308.32 rows=1213195 width=30) (actual time=877.728..9038.750 rows=1193605 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=204619 read=86714 dirtied=144 written=1453 -> Seq Scan on orders (cost=0.00..407703.43 rows=15164943 width=8) (actual time=0.006..3077.840 rows=15000000 loops=1) Buffers: shared hit=204616 read=51438 dirtied=144 written=1436 -> Hash (cost=57104.40..57104.40 rows=120000 width=30) (actual time=877.214..877.214 rows=119836 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 8280kB Buffers: shared hit=3 read=35276 written=17 -> Hash Join (cost=1.40..57104.40 rows=120000 width=30) (actual time=0.036..831.107 rows=119836 loops=1) Hash Cond: (customer.c_nationkey = n2.n_nationkey) Buffers: shared hit=3 read=35276 written=17 -> Seq Scan on customer (cost=0.00..50278.00 rows=1500000 width=8) (actual time=0.005..587.925 rows=1500000 loops=1) Buffers: shared hit=2 read=35276 written=17 -> Hash (cost=1.38..1.38 rows=2 width=30) (actual time=0.019..0.019 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=0.013..0.016 rows=2 loops=1) Filter: ((n_name = 'ROMANIA'::bpchar) OR (n_name = 'PERU'::bpchar)) Rows Removed by Filter: 23 Buffers: shared hit=1 -> Index Scan using pk_lineitem on lineitem (cost=0.56..1.27 rows=5 width=20) (actual time=0.010..0.011 rows=1 loops=1193605) Index Cond: (l_orderkey = orders.o_orderkey) Filter: ((l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Rows Removed by Filter: 3 Buffers: shared hit=5474520 read=578728 written=8980 -> Hash (cost=3635.40..3635.40 rows=8000 width=30) (actual time=47.574..47.574 rows=8020 loops=1) Buckets: 8192 Batches: 1 Memory Usage: 550kB Buffers: shared hit=2180 -> Hash Join (cost=1.40..3635.40 rows=8000 width=30) (actual time=0.034..45.323 rows=8020 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=0.005..29.109 rows=100000 loops=1) Buffers: shared hit=2179 -> Hash (cost=1.38..1.38 rows=2 width=30) (actual time=0.020..0.020 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=0.012..0.014 rows=2 loops=1) Filter: ((n_name = 'PERU'::bpchar) OR (n_name = 'ROMANIA'::bpchar)) Rows Removed by Filter: 23 Buffers: shared hit=1 Planning time: 5.433 ms Execution time: 23666.671 ms (56 rows) COMMIT; COMMIT