BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'GERMANY' 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 = 'SMALL BURNISHED BRASS' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2178490.29..2178492.12 rows=731 width=38) (actual time=13487.820..13487.821 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=816137 read=187461 -> HashAggregate (cost=2178442.73..2178455.52 rows=731 width=38) (actual time=13487.767..13487.768 rows=2 loops=1) Buffers: shared hit=816134 read=187461 -> Nested Loop (cost=495286.65..2177953.53 rows=24460 width=38) (actual time=9477.705..13457.851 rows=24241 loops=1) Buffers: shared hit=816134 read=187461 -> Nested Loop (cost=495286.65..2170977.53 rows=24460 width=16) (actual time=9477.659..13399.144 rows=24241 loops=1) Buffers: shared hit=767652 read=187461 -> Hash Join (cost=495286.65..2163854.70 rows=24460 width=16) (actual time=9477.608..13197.937 rows=24241 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=697251 read=185012 -> Nested Loop (cost=0.00..1666309.98 rows=402695 width=16) (actual time=1.193..3237.049 rows=402885 loops=1) Buffers: shared hit=313495 read=156610 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..46582.72 rows=13413 width=4) (actual time=0.710..145.765 rows=13399 loops=1) Index Cond: (p_type = 'SMALL BURNISHED BRASS'::text) Heap Fetches: 13399 Buffers: shared read=11553 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.45 rows=31 width=20) (actual time=0.025..0.223 rows=30 loops=13399) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=313495 read=145057 -> Hash (cost=483886.33..483886.33 rows=912025 width=8) (actual time=9475.319..9475.319 rows=913948 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35702kB Buffers: shared hit=383753 read=28402 -> Hash Join (cost=135741.78..483886.33 rows=912025 width=8) (actual time=1939.893..9177.424 rows=913948 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=383753 read=28402 -> Bitmap Heap Scan on orders (cost=96711.16..418635.00 rows=4560123 width=12) (actual time=1321.100..4052.469 rows=4561961 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=238409 read=27569 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..95571.13 rows=4560123 width=0) (actual time=1231.755..1231.755 rows=4561961 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared read=12456 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=618.520..618.520 rows=300963 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10581kB Buffers: shared hit=145344 read=833 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=31.373..551.559 rows=300963 loops=1) Buffers: shared hit=145344 read=833 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.025..0.071 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=0.004..0.016 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.012..0.012 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=0.008..0.009 rows=1 loops=1) Filter: (r_name = 'EUROPE'::bpchar) Rows Removed by Filter: 4 Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=905.09..6455.63 rows=60000 width=8) (actual time=19.102..100.513 rows=60193 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=145342 read=833 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=13.516..13.516 rows=60193 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=6 read=833 -> Index Scan using pk_supplier on supplier (cost=0.00..0.28 rows=1 width=8) (actual time=0.007..0.007 rows=1 loops=24241) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=70401 read=2449 -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) (actual time=0.001..0.001 rows=1 loops=24241) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=48482 Total runtime: 13496.746 ms (64 rows) COMMIT; COMMIT