BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'JAPAN' 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 = 'ASIA' and s_nationkey = n2.n_nationkey and o_orderdate between date '1995-01-01' and date '1996-12-31' and p_type = 'MEDIUM PLATED NICKEL' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2220114.13..2220115.96 rows=731 width=38) (actual time=28296.859..28296.859 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=791354 read=213088 dirtied=2255 written=1 -> HashAggregate (cost=2220066.56..2220079.36 rows=731 width=38) (actual time=28296.757..28296.758 rows=2 loops=1) Buffers: shared hit=791351 read=213088 dirtied=2255 written=1 -> Nested Loop (cost=501116.63..2219562.18 rows=25219 width=38) (actual time=20293.519..28228.944 rows=24364 loops=1) Buffers: shared hit=791351 read=213088 dirtied=2255 written=1 -> Nested Loop (cost=501116.63..2212369.72 rows=25219 width=16) (actual time=20293.469..28042.733 rows=24364 loops=1) Buffers: shared hit=742623 read=213088 dirtied=2255 written=1 -> Hash Join (cost=501116.63..2205025.89 rows=25219 width=16) (actual time=20293.436..27686.452 rows=24364 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=669406 read=213088 dirtied=2255 written=1 -> Nested Loop (cost=0.00..1701580.02 rows=415411 width=16) (actual time=0.822..6462.746 rows=398031 loops=1) Buffers: shared hit=268709 read=198864 dirtied=2255 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..47516.57 rows=13727 width=4) (actual time=0.471..269.728 rows=13254 loops=1) Index Cond: (p_type = 'MEDIUM PLATED NICKEL'::text) Heap Fetches: 13254 Buffers: shared hit=2 read=11371 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.19 rows=31 width=20) (actual time=0.047..0.451 rows=30 loops=13254) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=268707 read=187493 dirtied=2255 -> Hash (cost=489631.26..489631.26 rows=918830 width=8) (actual time=20290.603..20290.603 rows=913305 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35676kB Buffers: shared hit=400694 read=14224 written=1 -> Hash Join (cost=138754.64..489631.26 rows=918830 width=8) (actual time=4326.050..19788.447 rows=913305 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=400694 read=14224 written=1 -> Bitmap Heap Scan on orders (cost=99724.02..424184.27 rows=4594150 width=12) (actual time=2829.682..7144.359 rows=4561632 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=255287 read=13393 written=1 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..98575.48 rows=4594150 width=0) (actual time=2717.616..2717.616 rows=4598186 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared read=13132 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=1496.108..1496.108 rows=300270 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10557kB Buffers: shared hit=145407 read=831 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=35.372..1323.690 rows=300270 loops=1) Buffers: shared hit=145407 read=831 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.036..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=0.007..0.026 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.017..0.017 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..0.016 rows=1 loops=1) Filter: (r_name = 'ASIA'::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=33.495..244.368 rows=60054 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=145405 read=831 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=23.330..23.330 rows=60054 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=5 read=831 -> 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=24364) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=73217 -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) (actual time=0.004..0.005 rows=1 loops=24364) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=48728 Total runtime: 28307.123 ms (64 rows) COMMIT; COMMIT