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 = 'GERMANY' and n2.n_name = 'ALGERIA') or (n1.n_name = 'ALGERIA' and n2.n_name = 'GERMANY') ) 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=2374148.41..2376058.67 rows=58777 width=64) (actual time=101454.161..101477.767 rows=4 loops=1) Buffers: shared hit=729159 read=713436 written=3526 -> Sort (cost=2374148.41..2374295.36 rows=58777 width=64) (actual time=101445.903..101450.230 rows=57974 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: 9689kB Buffers: shared hit=729159 read=713436 written=3526 -> Hash Join (cost=900595.06..2369492.40 rows=58777 width=64) (actual time=56573.601..100837.781 rows=57974 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (n1.n_nationkey = supplier.s_nationkey)) Buffers: shared hit=729151 read=713436 written=3526 -> Hash Join (cost=895916.06..2334543.35 rows=1469420 width=72) (actual time=56490.271..97576.304 rows=1462449 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=726969 read=713436 written=3526 -> Bitmap Heap Scan on lineitem (cost=387459.02..1742457.89 rows=18382458 width=20) (actual time=16633.324..36563.702 rows=18246498 loops=1) Recheck Cond: ((l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Buffers: shared hit=528614 read=596841 written=253 -> Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx (cost=0.00..382863.41 rows=18382458 width=0) (actual time=15853.856..15853.856 rows=18466868 loops=1) Index Cond: ((l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Buffers: shared hit=173 read=49642 written=33 -> Hash (cost=493274.29..493274.29 rows=1214620 width=60) (actual time=39856.072..39856.072 rows=1201327 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 107932kB Buffers: shared hit=198355 read=116595 written=3273 -> Hash Join (cost=15638.06..493274.29 rows=1214620 width=60) (actual time=1325.182..37722.285 rows=1201327 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=198355 read=116595 written=3273 -> Seq Scan on orders (cost=0.00..408509.11 rows=15194911 width=8) (actual time=0.025..6894.712 rows=15015000 loops=1) Buffers: shared hit=174502 read=82058 written=3202 -> Hash (cost=14139.26..14139.26 rows=119904 width=60) (actual time=1325.003..1325.003 rows=120069 loops=1) Buckets: 16384 Batches: 1 Memory Usage: 10788kB Buffers: shared hit=23853 read=34537 written=71 -> Nested Loop (cost=905.09..14139.26 rows=119904 width=60) (actual time=21.954..1214.295 rows=120069 loops=1) Buffers: shared hit=23853 read=34537 written=71 -> Nested Loop (cost=0.00..28.00 rows=2 width=60) (actual time=0.101..0.497 rows=2 loops=1) Join Filter: (((n1.n_name = 'GERMANY'::bpchar) AND (n2.n_name = 'ALGERIA'::bpchar)) OR ((n1.n_name = 'ALGERIA'::bpchar) AND (n2.n_name = 'GERMANY'::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=0.022..0.048 rows=25 loops=1) Buffers: shared hit=2 -> Materialize (cost=0.00..1.38 rows=25 width=30) (actual time=0.002..0.005 rows=25 loops=25) Buffers: shared hit=1 -> Seq Scan on nation n2 (cost=0.00..1.25 rows=25 width=30) (actual time=0.031..0.041 rows=25 loops=1) Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=905.09..6455.63 rows=60000 width=8) (actual time=26.598..581.999 rows=60034 loops=2) Recheck Cond: (c_nationkey = n2.n_nationkey) Buffers: shared hit=23850 read=34537 written=71 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=18.385..18.385 rows=60034 loops=2) Index Cond: (c_nationkey = n2.n_nationkey) Buffers: shared hit=1 read=333 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=82.547..82.547 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=0.012..51.301 rows=100000 loops=1) Buffers: shared hit=2179 Total runtime: 101510.436 ms (53 rows) COMMIT; COMMIT