BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'VIETNAM' 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 = 'ASIA' and s_nationkey = n2.n_nationkey and o_orderdate between date '1995-01-01' and date '1996-12-31' and p_type = 'SMALL BRUSHED COPPER' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2143267.46..2143269.28 rows=728 width=38) (actual time=47151.786..47151.786 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=727537 read=274630 dirtied=785 written=2809 -> HashAggregate (cost=2143220.11..2143232.85 rows=728 width=38) (actual time=47151.715..47151.716 rows=2 loops=1) Buffers: shared hit=727534 read=274630 dirtied=785 written=2809 -> Nested Loop (cost=496018.70..2142743.91 rows=23810 width=38) (actual time=34908.152..47070.243 rows=24410 loops=1) Buffers: shared hit=727534 read=274630 dirtied=785 written=2809 -> Nested Loop (cost=496018.70..2135953.30 rows=23810 width=16) (actual time=34908.033..46814.606 rows=24410 loops=1) Buffers: shared hit=678714 read=274630 dirtied=785 written=2809 -> Hash Join (cost=496018.70..2129017.43 rows=23818 width=16) (actual time=34907.991..46219.914 rows=24410 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=605366 read=274630 dirtied=785 written=2809 -> Nested Loop (cost=0.00..1630789.99 rows=394113 width=16) (actual time=2.589..10170.777 rows=398081 loops=1) Buffers: shared hit=276556 read=190179 dirtied=785 written=315 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..45565.00 rows=13073 width=4) (actual time=2.526..411.280 rows=13250 loops=1) Index Cond: (p_type = 'SMALL BRUSHED COPPER'::text) Heap Fetches: 13250 Buffers: shared hit=10 read=11381 written=22 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.95 rows=31 width=20) (actual time=0.076..0.720 rows=30 loops=13250) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=276546 read=178798 dirtied=785 written=293 -> Hash (cost=484630.62..484630.62 rows=911046 width=8) (actual time=34904.004..34904.004 rows=912405 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35641kB Buffers: shared hit=328807 read=84451 written=2494 -> Hash Join (cost=135575.62..484630.62 rows=911046 width=8) (actual time=9296.287..34245.061 rows=912405 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=328807 read=84451 written=2494 -> Bitmap Heap Scan on orders (cost=96545.00..419407.43 rows=4555229 width=12) (actual time=4291.602..15369.876 rows=4557142 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=218544 read=48476 written=1987 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..95406.19 rows=4555229 width=0) (actual time=4165.042..4165.042 rows=4579958 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared read=12486 written=529 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=5004.476..5004.476 rows=300270 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10557kB Buffers: shared hit=110263 read=35975 written=507 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=51.802..4771.581 rows=300270 loops=1) Buffers: shared hit=110263 read=35975 written=507 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.046..0.103 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..0.023 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.021..0.021 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=0.017..0.018 rows=1 loops=1) Filter: (r_name = 'ASIA'::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=44.855..930.992 rows=60054 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=110261 read=35975 written=507 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=34.489..34.489 rows=60054 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=5 read=831 written=29 -> Index Scan using pk_supplier on supplier (cost=0.00..0.28 rows=1 width=8) (actual time=0.022..0.022 rows=1 loops=24410) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=73348 -> 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=24410) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=48820 Total runtime: 47164.930 ms (64 rows) COMMIT; COMMIT