BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'CANADA' 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 = 'SMALL ANODIZED TIN' ) as all_nations group by o_year order by o_year; QUERY PLAN ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1754463.58..1754465.41 rows=729 width=38) (actual time=11160.804..11160.805 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=1776627 read=243146 dirtied=66 written=310 -> HashAggregate (cost=1754416.16..1754428.92 rows=729 width=38) (actual time=11160.735..11160.737 rows=2 loops=1) Group Key: date_part('year'::text, (orders.o_orderdate)::timestamp without time zone) Buffers: shared hit=1776624 read=243146 dirtied=66 written=310 -> Hash Join (cost=39455.05..1753918.92 rows=24862 width=38) (actual time=1772.091..11119.300 rows=24342 loops=1) Hash Cond: (supplier.s_nationkey = n2.n_nationkey) Buffers: shared hit=1776624 read=243146 dirtied=66 written=310 -> Nested Loop (cost=39453.49..1753451.20 rows=24862 width=16) (actual time=1772.031..11083.097 rows=24342 loops=1) Buffers: shared hit=1776620 read=243146 dirtied=66 written=310 -> Hash Join (cost=39453.20..1745429.18 rows=24862 width=16) (actual time=1772.012..10870.307 rows=24342 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=1703461 read=243146 dirtied=66 written=310 -> Nested Loop (cost=422.51..1705683.71 rows=124309 width=20) (actual time=7.370..9021.178 rows=121999 loops=1) Buffers: shared hit=1593624 read=207046 dirtied=66 written=248 -> Nested Loop (cost=422.08..1504644.94 rows=410567 width=16) (actual time=7.302..4501.129 rows=401903 loops=1) Buffers: shared hit=289889 read=181677 written=220 -> Bitmap Heap Scan on part (cost=417.36..28370.52 rows=13540 width=4) (actual time=7.158..167.563 rows=13380 loops=1) Recheck Cond: ((p_type)::text = 'SMALL ANODIZED TIN'::text) Heap Blocks: exact=11423 Buffers: shared hit=1866 read=9626 written=15 -> Bitmap Index Scan on part_p_type_p_partkey_idx (cost=0.00..413.98 rows=13540 width=0) (actual time=4.820..4.820 rows=13380 loops=1) Index Cond: ((p_type)::text = 'SMALL ANODIZED TIN'::text) Buffers: shared read=69 -> Bitmap Heap Scan on lineitem (cost=4.72..108.72 rows=31 width=20) (actual time=0.044..0.312 rows=30 loops=13380) Recheck Cond: (l_partkey = part.p_partkey) Heap Blocks: exact=404535 Buffers: shared hit=288023 read=172051 written=205 -> Bitmap Index Scan on lineitem_l_partkey_l_quantity_l_shipmode_idx (cost=0.00..4.71 rows=31 width=0) (actual time=0.027..0.027 rows=30 loops=13380) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=39560 read=15979 written=19 -> Index Scan using orders_o_orderkey_o_orderdate_idx on orders (cost=0.43..0.48 rows=1 width=12) (actual time=0.010..0.011 rows=0 loops=401903) Index Cond: ((o_orderkey = lineitem.l_orderkey) AND (o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=1303735 read=25369 dirtied=66 written=28 -> Hash (cost=35280.69..35280.69 rows=300000 width=4) (actual time=1145.502..1145.502 rows=299436 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 14624kB Buffers: shared hit=109837 read=36100 written=62 -> Nested Loop (cost=906.18..35280.69 rows=300000 width=4) (actual time=20.838..1050.335 rows=299436 loops=1) Buffers: shared hit=109837 read=36100 written=62 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.078..0.107 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=0.015..0.026 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.024..0.024 rows=1 loops=1) Buckets: 1024 Batches: 1 Memory Usage: 9kB Buffers: shared hit=1 -> Seq Scan on region (cost=0.00..1.06 rows=1 width=4) (actual time=0.017..0.018 rows=1 loops=1) Filter: (r_name = 'AMERICA'::bpchar) Rows Removed by Filter: 4 Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=905.11..6455.64 rows=60000 width=8) (actual time=18.620..198.908 rows=59887 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Heap Blocks: exact=145102 Buffers: shared hit=109835 read=36100 written=62 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=12.216..12.216 rows=59887 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=7 read=826 written=1 -> Index Scan using pk_supplier on supplier (cost=0.29..0.31 rows=1 width=8) (actual time=0.007..0.008 rows=1 loops=24342) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=73159 -> Hash (cost=1.25..1.25 rows=25 width=30) (actual time=0.021..0.021 rows=25 loops=1) Buckets: 1024 Batches: 1 Memory Usage: 10kB Buffers: shared hit=1 -> Seq Scan on nation n2 (cost=0.00..1.25 rows=25 width=30) (actual time=0.003..0.004 rows=25 loops=1) Buffers: shared hit=1 Planning time: 8.478 ms Execution time: 11161.803 ms (70 rows) COMMIT; COMMIT