BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'ROMANIA' 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 = 'MEDIUM BRUSHED COPPER' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2170636.74..2170638.57 rows=731 width=38) (actual time=32498.781..32498.781 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=771098 read=232053 dirtied=1165 written=1379 -> HashAggregate (cost=2170589.18..2170601.97 rows=731 width=38) (actual time=32498.709..32498.711 rows=2 loops=1) Buffers: shared hit=771095 read=232053 dirtied=1165 written=1379 -> Nested Loop (cost=497048.44..2170101.20 rows=24399 width=38) (actual time=23298.120..32421.859 rows=24286 loops=1) Buffers: shared hit=771095 read=232053 dirtied=1165 written=1379 -> Nested Loop (cost=497048.44..2163142.60 rows=24399 width=16) (actual time=23298.054..32172.461 rows=24286 loops=1) Buffers: shared hit=722523 read=232053 dirtied=1165 written=1379 -> Hash Join (cost=497048.44..2156037.55 rows=24399 width=16) (actual time=23298.007..31719.412 rows=24286 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=649532 read=232053 dirtied=1165 written=1379 -> Nested Loop (cost=0.00..1656736.70 rows=401684 width=16) (actual time=0.453..7032.515 rows=399192 loops=1) Buffers: shared hit=286623 read=181614 dirtied=1165 written=42 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..46280.97 rows=13313 width=4) (actual time=0.328..280.110 rows=13305 loops=1) Index Cond: (p_type = 'MEDIUM BRUSHED COPPER'::text) Heap Fetches: 13305 Buffers: shared hit=1572 read=9871 written=1 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.66 rows=31 width=20) (actual time=0.053..0.490 rows=30 loops=13305) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=285051 read=171743 dirtied=1165 written=41 -> Hash (cost=485602.63..485602.63 rows=915665 width=8) (actual time=23296.716..23296.716 rows=912880 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35660kB Buffers: shared hit=362906 read=50439 written=1337 -> Hash Join (cost=136068.36..485602.63 rows=915665 width=8) (actual time=5206.955..22548.925 rows=912880 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=362906 read=50439 written=1337 -> Bitmap Heap Scan on orders (cost=97037.74..420246.63 rows=4578326 width=12) (actual time=3721.157..8734.869 rows=4557142 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=217669 read=49499 written=1266 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..95893.16 rows=4578326 width=0) (actual time=3586.351..3586.351 rows=4584480 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=1026 read=11608 written=1221 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=1485.551..1485.551 rows=300963 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10581kB Buffers: shared hit=145237 read=940 written=71 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=33.528..1305.597 rows=300963 loops=1) Buffers: shared hit=145237 read=940 written=71 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.043..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=0.008..0.023 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.020..0.020 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 = '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=33.772..241.166 rows=60193 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=145235 read=940 written=71 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=23.307..23.307 rows=60193 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=6 read=833 written=67 -> Index Scan using pk_supplier on supplier (cost=0.00..0.28 rows=1 width=8) (actual time=0.016..0.016 rows=1 loops=24286) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=72991 -> 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=24286) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=48572 Total runtime: 32518.390 ms (64 rows) COMMIT; COMMIT