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 = 'MOROCCO' and n2.n_name = 'KENYA') or (n1.n_name = 'KENYA' and n2.n_name = 'MOROCCO') ) 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=2365492.32..2367398.84 rows=58662 width=64) (actual time=82312.092..82341.101 rows=4 loops=1) Buffers: shared hit=1110064 read=324679 written=5014 -> Sort (cost=2365492.32..2365638.98 rows=58662 width=64) (actual time=82302.460..82309.710 rows=58363 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: 9744kB Buffers: shared hit=1110064 read=324679 written=5014 -> Hash Join (cost=898613.01..2360846.25 rows=58662 width=64) (actual time=47980.292..81993.032 rows=58363 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (n1.n_nationkey = supplier.s_nationkey)) Buffers: shared hit=1110056 read=324679 written=5014 -> Hash Join (cost=893934.01..2325918.30 rows=1468451 width=72) (actual time=47851.801..78722.806 rows=1454706 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=1107874 read=324679 written=5014 -> Bitmap Heap Scan on lineitem (cost=388394.76..1736805.79 rows=18370335 width=20) (actual time=14791.859..27524.442 rows=18247310 loops=1) Recheck Cond: ((l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Buffers: shared hit=923527 read=195543 written=384 -> Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx (cost=0.00..383802.18 rows=18370335 width=0) (actual time=14150.984..14150.984 rows=18360093 loops=1) Index Cond: ((l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Buffers: shared hit=3338 read=46477 written=384 -> Hash (cost=490446.39..490446.39 rows=1207429 width=60) (actual time=33059.067..33059.067 rows=1194759 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 107342kB Buffers: shared hit=184347 read=129136 written=4630 -> Hash Join (cost=15638.06..490446.39 rows=1207429 width=60) (actual time=1106.574..32277.143 rows=1194759 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=184347 read=129136 written=4630 -> Seq Scan on orders (cost=0.00..406090.48 rows=15104948 width=8) (actual time=0.022..5845.661 rows=15015000 loops=1) Buffers: shared hit=160493 read=94548 written=2336 -> Hash (cost=14139.26..14139.26 rows=119904 width=60) (actual time=1106.404..1106.404 rows=119310 loops=1) Buckets: 16384 Batches: 1 Memory Usage: 10720kB Buffers: shared hit=23854 read=34588 written=2294 -> Nested Loop (cost=905.09..14139.26 rows=119904 width=60) (actual time=21.324..1015.113 rows=119310 loops=1) Buffers: shared hit=23854 read=34588 written=2294 -> Nested Loop (cost=0.00..28.00 rows=2 width=60) (actual time=0.220..0.422 rows=2 loops=1) Join Filter: (((n1.n_name = 'MOROCCO'::bpchar) AND (n2.n_name = 'KENYA'::bpchar)) OR ((n1.n_name = 'KENYA'::bpchar) AND (n2.n_name = 'MOROCCO'::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=0.024..0.046 rows=25 loops=1) Buffers: shared hit=2 -> Materialize (cost=0.00..1.38 rows=25 width=30) (actual time=0.001..0.004 rows=25 loops=25) Buffers: shared hit=1 -> Seq Scan on nation n2 (cost=0.00..1.25 rows=25 width=30) (actual time=0.008..0.012 rows=25 loops=1) Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=905.09..6455.63 rows=60000 width=8) (actual time=26.655..486.085 rows=59655 loops=2) Recheck Cond: (c_nationkey = n2.n_nationkey) Buffers: shared hit=23851 read=34588 written=2294 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=18.021..18.021 rows=59655 loops=2) Index Cond: (c_nationkey = n2.n_nationkey) Buffers: shared hit=3 read=330 written=27 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=127.748..127.748 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=0.015..78.818 rows=100000 loops=1) Buffers: shared hit=2179 Total runtime: 82361.058 ms (53 rows) COMMIT; COMMIT