BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'RUSSIA' 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 = 'EUROPE' and s_nationkey = n2.n_nationkey and o_orderdate between date '1995-01-01' and date '1996-12-31' and p_type = 'ECONOMY BURNISHED BRASS' ) as all_nations group by o_year order by o_year; QUERY PLAN ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1779905.13..1779906.95 rows=729 width=38) (actual time=10126.261..10126.262 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=1820469 read=214391 dirtied=1659 written=4115 -> HashAggregate (cost=1779857.71..1779870.46 rows=729 width=38) (actual time=10126.202..10126.203 rows=2 loops=1) Group Key: date_part('year'::text, (orders.o_orderdate)::timestamp without time zone) Buffers: shared hit=1820466 read=214391 dirtied=1659 written=4115 -> Hash Join (cost=39460.61..1779353.03 rows=25234 width=38) (actual time=848.667..10086.563 rows=24560 loops=1) Hash Cond: (supplier.s_nationkey = n2.n_nationkey) Buffers: shared hit=1820466 read=214391 dirtied=1659 written=4115 -> Nested Loop (cost=39459.05..1778878.33 rows=25234 width=16) (actual time=848.589..10052.059 rows=24560 loops=1) Buffers: shared hit=1820462 read=214391 dirtied=1659 written=4115 -> Hash Join (cost=39458.75..1770736.27 rows=25234 width=16) (actual time=848.565..9844.829 rows=24560 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=1746675 read=214391 dirtied=1659 written=4115 -> Nested Loop (cost=428.07..1730980.10 rows=126171 width=20) (actual time=8.161..8926.719 rows=122938 loops=1) Buffers: shared hit=1600499 read=214391 dirtied=1659 written=4115 -> Nested Loop (cost=427.63..1526937.67 rows=416718 width=16) (actual time=7.784..4422.150 rows=404992 loops=1) Buffers: shared hit=290013 read=185501 dirtied=1659 written=3541 -> Bitmap Heap Scan on part (cost=427.07..28637.97 rows=13760 width=4) (actual time=7.725..155.916 rows=13476 loops=1) Recheck Cond: ((p_type)::text = 'ECONOMY BURNISHED BRASS'::text) Heap Blocks: exact=11540 Buffers: shared hit=4366 read=7258 written=152 -> Bitmap Index Scan on part_p_type_p_partkey_idx (cost=0.00..423.63 rows=13760 width=0) (actual time=5.253..5.253 rows=13476 loops=1) Index Cond: ((p_type)::text = 'ECONOMY BURNISHED BRASS'::text) Buffers: shared hit=1 read=83 written=2 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.56..108.58 rows=31 width=20) (actual time=0.029..0.306 rows=30 loops=13476) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=285647 read=178243 dirtied=1659 written=3389 -> Index Scan using orders_o_orderkey_o_orderdate_idx on orders (cost=0.43..0.48 rows=1 width=12) (actual time=0.010..0.010 rows=0 loops=404992) Index Cond: ((o_orderkey = lineitem.l_orderkey) AND (o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=1310486 read=28890 written=574 -> Hash (cost=35280.69..35280.69 rows=300000 width=4) (actual time=835.087..835.087 rows=300963 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 14677kB Buffers: shared hit=146176 -> Nested Loop (cost=906.18..35280.69 rows=300000 width=4) (actual time=20.089..742.097 rows=300963 loops=1) Buffers: shared hit=146176 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.060..0.092 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=0.010..0.017 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: 9kB 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 = 'EUROPE'::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=17.697..137.467 rows=60193 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Heap Blocks: exact=145336 Buffers: shared hit=146174 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=10.874..10.874 rows=60193 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=838 -> Index Scan using pk_supplier on supplier (cost=0.29..0.31 rows=1 width=8) (actual time=0.007..0.007 rows=1 loops=24560) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=73787 -> Hash (cost=1.25..1.25 rows=25 width=30) (actual time=0.025..0.025 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=0.007..0.010 rows=25 loops=1) Buffers: shared hit=1 Planning time: 7.564 ms Execution time: 10127.104 ms (66 rows) COMMIT; COMMIT