BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'PERU' then volume else 0 end) / sum(volume) as mkt_share from ( select extract(year from o_orderdate) as o_year, l_extendedprice * (1 - l_discount) as volume, n2.n_name as nation from part, supplier, lineitem, orders, customer, nation n1, nation n2, region where p_partkey = l_partkey and s_suppkey = l_suppkey and l_orderkey = o_orderkey and o_custkey = c_custkey and c_nationkey = n1.n_nationkey and n1.n_regionkey = r_regionkey and r_name = 'AMERICA' and s_nationkey = n2.n_nationkey and o_orderdate between date '1995-01-01' and date '1996-12-31' and p_type = 'MEDIUM POLISHED NICKEL' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2154204.33..2154206.16 rows=733 width=38) (actual time=35748.105..35748.106 rows=2 loops=1) Sort Key: (date_part('year'::text, (orders.o_orderdate)::timestamp without time zone)) Sort Method: quicksort Memory: 25kB Buffers: shared hit=726052 read=284516 dirtied=1002 written=121 -> HashAggregate (cost=2154156.62..2154169.44 rows=733 width=38) (actual time=35748.014..35748.015 rows=2 loops=1) Buffers: shared hit=726049 read=284516 dirtied=1002 written=121 -> Nested Loop (cost=497422.31..2153673.84 rows=24139 width=38) (actual time=26002.015..35671.695 rows=24762 loops=1) Buffers: shared hit=726049 read=284516 dirtied=1002 written=121 -> Nested Loop (cost=497422.31..2146789.39 rows=24139 width=16) (actual time=26001.947..35424.391 rows=24762 loops=1) Buffers: shared hit=676525 read=284516 dirtied=1002 written=121 -> Hash Join (cost=497422.31..2139760.05 rows=24139 width=16) (actual time=26001.899..34966.007 rows=24762 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=602111 read=284516 dirtied=1002 written=121 -> Nested Loop (cost=0.00..1640112.95 rows=396679 width=16) (actual time=0.492..7686.764 rows=404465 loops=1) Buffers: shared hit=252882 read=220784 dirtied=748 written=118 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..45822.34 rows=13160 width=4) (actual time=0.365..315.140 rows=13497 loops=1) Index Cond: (p_type = 'MEDIUM POLISHED NICKEL'::text) Heap Fetches: 13497 Buffers: shared hit=1 read=11586 written=12 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.84 rows=31 width=20) (actual time=0.054..0.530 rows=30 loops=13497) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=252881 read=209198 dirtied=748 written=106 -> Hash (cost=485955.46..485955.46 rows=917348 width=8) (actual time=26000.226..26000.226 rows=911211 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35595kB Buffers: shared hit=349226 read=63732 dirtied=254 written=3 -> Hash Join (cost=136246.61..485955.46 rows=917348 width=8) (actual time=6761.162..25180.514 rows=911211 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=349226 read=63732 dirtied=254 written=3 -> Bitmap Heap Scan on orders (cost=97215.98..420551.08 rows=4586740 width=12) (actual time=3933.132..9919.287 rows=4561668 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=239389 read=27631 dirtied=254 written=3 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..96069.30 rows=4586740 width=0) (actual time=3806.766..3806.766 rows=4579958 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared read=12486 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=2827.790..2827.790 rows=299436 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10528kB Buffers: shared hit=109837 read=36101 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=37.331..2618.770 rows=299436 loops=1) Buffers: shared hit=109837 read=36101 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.040..0.126 rows=5 loops=1) Hash Cond: (n1.n_regionkey = region.r_regionkey) Buffers: shared hit=2 -> Seq Scan on nation n1 (cost=0.00..1.25 rows=25 width=8) (actual time=0.009..0.029 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.019..0.019 rows=1 loops=1) Buckets: 1024 Batches: 1 Memory Usage: 1kB Buffers: shared hit=1 -> Seq Scan on region (cost=0.00..1.06 rows=1 width=4) (actual time=0.016..0.017 rows=1 loops=1) Filter: (r_name = 'AMERICA'::bpchar) Rows Removed by Filter: 4 Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=905.09..6455.63 rows=60000 width=8) (actual time=35.413..502.357 rows=59887 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=109835 read=36101 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=24.811..24.811 rows=59887 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=7 read=827 -> Index Scan using pk_supplier on supplier (cost=0.00..0.28 rows=1 width=8) (actual time=0.016..0.016 rows=1 loops=24762) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=74414 -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) (actual time=0.006..0.007 rows=1 loops=24762) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=49524 Total runtime: 35768.607 ms (64 rows) COMMIT; COMMIT