BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'VIETNAM' 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 = 'STANDARD ANODIZED STEEL' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2160990.43..2160992.26 rows=729 width=38) (actual time=28444.372..28444.373 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=778483 read=224959 dirtied=2749 written=489 -> HashAggregate (cost=2160943.01..2160955.77 rows=729 width=38) (actual time=28444.280..28444.282 rows=2 loops=1) Buffers: shared hit=778480 read=224959 dirtied=2749 written=489 -> Nested Loop (cost=500956.66..2160460.39 rows=24131 width=38) (actual time=21556.248..28386.944 rows=24255 loops=1) Buffers: shared hit=778480 read=224959 dirtied=2749 written=489 -> Nested Loop (cost=500956.66..2153578.23 rows=24131 width=16) (actual time=21556.173..28243.807 rows=24255 loops=1) Buffers: shared hit=729970 read=224959 dirtied=2749 written=489 -> Hash Join (cost=500956.66..2146542.21 rows=24162 width=16) (actual time=21556.126..27942.663 rows=24255 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=657077 read=224959 dirtied=2749 written=489 -> Nested Loop (cost=0.00..1643347.68 rows=399248 width=16) (actual time=0.436..5138.516 rows=397028 loops=1) Buffers: shared hit=271379 read=195467 dirtied=2497 written=303 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..45882.97 rows=13180 width=4) (actual time=0.342..212.070 rows=13234 loops=1) Index Cond: (p_type = 'STANDARD ANODIZED STEEL'::text) Heap Fetches: 13234 Buffers: shared hit=10 read=11345 written=23 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.89 rows=31 width=20) (actual time=0.036..0.359 rows=30 loops=13234) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=271369 read=184122 dirtied=2497 written=280 -> Hash (cost=489495.84..489495.84 rows=916866 width=8) (actual time=21554.168..21554.168 rows=913270 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35675kB Buffers: shared hit=385695 read=29492 dirtied=252 written=186 -> Hash Join (cost=138569.99..489495.84 rows=916866 width=8) (actual time=4660.785..20033.609 rows=913270 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=385695 read=29492 dirtied=252 written=186 -> Bitmap Heap Scan on orders (cost=99539.37..424105.32 rows=4584330 width=12) (actual time=3326.397..7437.539 rows=4561673 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=254230 read=14719 dirtied=252 written=186 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..98393.29 rows=4584330 width=0) (actual time=3188.943..3188.943 rows=4602796 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=497 read=12651 written=181 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=1333.903..1333.903 rows=300270 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10557kB Buffers: shared hit=131465 read=14773 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=30.681..1175.638 rows=300270 loops=1) Buffers: shared hit=131465 read=14773 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.042..0.106 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=0.005..0.023 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=0.014..0.015 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=29.080..217.510 rows=60054 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=131463 read=14773 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=19.839..19.839 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=0.010..0.011 rows=1 loops=24255) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=72893 -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) (actual time=0.003..0.003 rows=1 loops=24255) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=48510 Total runtime: 28462.132 ms (64 rows) COMMIT; COMMIT