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 = 'LARGE BURNISHED NICKEL' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2182400.67..2182402.50 rows=731 width=38) (actual time=30161.940..30161.940 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=750866 read=263902 dirtied=1137 written=9 -> HashAggregate (cost=2182353.11..2182365.90 rows=731 width=38) (actual time=30161.868..30161.870 rows=2 loops=1) Buffers: shared hit=750863 read=263902 dirtied=1137 written=9 -> Nested Loop (cost=497993.26..2181861.71 rows=24570 width=38) (actual time=22779.867..30100.518 rows=24725 loops=1) Buffers: shared hit=750863 read=263902 dirtied=1137 written=9 -> Nested Loop (cost=497993.26..2174854.34 rows=24570 width=16) (actual time=22779.801..29937.093 rows=24725 loops=1) Buffers: shared hit=701413 read=263902 dirtied=1137 written=9 -> Hash Join (cost=497993.26..2167699.49 rows=24570 width=16) (actual time=22779.759..29621.111 rows=24725 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=627120 read=263902 dirtied=1137 written=9 -> Nested Loop (cost=0.00..1667436.99 rows=404709 width=16) (actual time=0.422..5774.141 rows=407652 loops=1) Buffers: shared hit=277317 read=200343 dirtied=1137 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..46583.08 rows=13413 width=4) (actual time=0.332..239.326 rows=13566 loops=1) Index Cond: (p_type = 'LARGE BURNISHED NICKEL'::text) Heap Fetches: 13566 Buffers: shared read=11646 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.53 rows=31 width=20) (actual time=0.041..0.394 rows=30 loops=13566) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=277317 read=188697 dirtied=1137 -> Hash (cost=486542.08..486542.08 rows=916094 width=8) (actual time=22778.399..22778.399 rows=911193 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35594kB Buffers: shared hit=349800 read=63559 written=9 -> Hash Join (cost=136710.35..486542.08 rows=916094 width=8) (actual time=5935.493..21975.965 rows=911193 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=349800 read=63559 written=9 -> Bitmap Heap Scan on orders (cost=97679.73..421173.76 rows=4580469 width=12) (actual time=3662.035..8348.545 rows=4561664 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=230470 read=36951 written=9 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..96534.61 rows=4580469 width=0) (actual time=3527.772..3527.772 rows=4584480 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared read=12634 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=2273.196..2273.196 rows=299436 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10528kB Buffers: shared hit=119330 read=26608 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=39.780..2092.178 rows=299436 loops=1) Buffers: shared hit=119330 read=26608 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.042..0.104 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=0.006..0.019 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.023..0.023 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=0.020..0.021 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=37.059..398.370 rows=59887 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=119328 read=26608 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=25.851..25.851 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=0.011..0.011 rows=1 loops=24725) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=74293 -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) (actual time=0.003..0.004 rows=1 loops=24725) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=49450 Total runtime: 30175.428 ms (64 rows) COMMIT; COMMIT