BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'UNITED STATES' 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 = 'STANDARD BRUSHED BRASS' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2167564.79..2167566.62 rows=731 width=38) (actual time=30524.217..30524.217 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=735876 read=265945 dirtied=2801 written=73 -> HashAggregate (cost=2167517.22..2167530.02 rows=731 width=38) (actual time=30524.137..30524.139 rows=2 loops=1) Buffers: shared hit=735873 read=265945 dirtied=2801 written=73 -> Nested Loop (cost=501710.99..2167030.26 rows=24348 width=38) (actual time=23548.526..30456.155 rows=24031 loops=1) Buffers: shared hit=735873 read=265945 dirtied=2801 written=73 -> Nested Loop (cost=501710.99..2160086.21 rows=24348 width=16) (actual time=23548.458..30292.525 rows=24031 loops=1) Buffers: shared hit=687811 read=265945 dirtied=2801 written=73 -> Hash Join (cost=501710.99..2152996.03 rows=24348 width=16) (actual time=23548.419..29948.785 rows=24031 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=615581 read=265945 dirtied=2801 written=73 -> Nested Loop (cost=0.00..1649037.28 rows=400856 width=16) (actual time=0.496..5226.913 rows=396928 loops=1) Buffers: shared hit=307968 read=158668 dirtied=2548 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..46043.58 rows=13233 width=4) (actual time=0.392..163.794 rows=13225 loops=1) Index Cond: (p_type = 'STANDARD BRUSHED BRASS'::text) Heap Fetches: 13225 Buffers: shared hit=5951 read=5428 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.83 rows=31 width=20) (actual time=0.040..0.367 rows=30 loops=13225) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=302017 read=153240 dirtied=2548 -> Hash (cost=490208.20..490208.20 rows=920223 width=8) (actual time=23546.081..23546.081 rows=911249 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35596kB Buffers: shared hit=307610 read=107277 dirtied=253 written=73 -> Hash Join (cost=138934.05..490208.20 rows=920223 width=8) (actual time=5616.862..22998.154 rows=911249 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=307610 read=107277 dirtied=253 written=73 -> Bitmap Heap Scan on orders (cost=99903.43..424721.17 rows=4601116 width=12) (actual time=3592.553..8685.224 rows=4561673 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=191757 read=77192 dirtied=253 written=56 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..98753.15 rows=4601116 width=0) (actual time=3418.816..3418.816 rows=4602796 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared read=13148 written=13 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=2024.053..2024.053 rows=299436 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10528kB Buffers: shared hit=115853 read=30085 written=17 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=34.257..1849.475 rows=299436 loops=1) Buffers: shared hit=115853 read=30085 written=17 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.038..0.098 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=0.007..0.015 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=0.015..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=31.379..351.170 rows=59887 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=115851 read=30085 written=17 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=21.249..21.249 rows=59887 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=7 read=827 written=1 -> Index Scan using pk_supplier on supplier (cost=0.00..0.28 rows=1 width=8) (actual time=0.012..0.012 rows=1 loops=24031) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=72230 -> 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=24031) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=48062 Total runtime: 30541.435 ms (64 rows) COMMIT; COMMIT