BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'CHINA' 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 = 'SMALL BRUSHED NICKEL' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2170491.39..2170493.22 rows=732 width=38) (actual time=70998.347..70998.348 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=726814 read=281370 dirtied=646 written=311 -> HashAggregate (cost=2170443.75..2170456.56 rows=732 width=38) (actual time=70998.257..70998.258 rows=2 loops=1) Buffers: shared hit=726811 read=281370 dirtied=646 written=311 -> Nested Loop (cost=496613.73..2169956.29 rows=24373 width=38) (actual time=41799.921..70864.688 rows=24340 loops=1) Buffers: shared hit=726811 read=281370 dirtied=646 written=311 -> Nested Loop (cost=496613.73..2163005.11 rows=24373 width=16) (actual time=41799.830..68989.171 rows=24340 loops=1) Buffers: shared hit=678131 read=281370 dirtied=646 written=311 -> Hash Join (cost=496613.73..2155906.45 rows=24377 width=16) (actual time=41799.780..67071.861 rows=24340 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=604985 read=281370 dirtied=646 written=311 -> Nested Loop (cost=0.00..1657043.48 rows=401096 width=16) (actual time=0.365..23788.511 rows=404147 loops=1) Buffers: shared hit=278775 read=194606 dirtied=398 written=31 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..46300.93 rows=13320 width=4) (actual time=0.206..895.857 rows=13487 loops=1) Index Cond: (p_type = 'SMALL BRUSHED NICKEL'::text) Heap Fetches: 13487 Buffers: shared hit=1895 read=9707 written=3 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.62 rows=31 width=20) (actual time=0.193..1.678 rows=30 loops=13487) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=276880 read=184899 dirtied=398 written=28 -> Hash (cost=485173.04..485173.04 rows=915255 width=8) (actual time=41797.420..41797.420 rows=912334 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35639kB Buffers: shared hit=326207 read=86764 dirtied=248 written=280 -> Hash Join (cost=135939.34..485173.04 rows=915255 width=8) (actual time=10047.013..41096.595 rows=912334 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=326207 read=86764 dirtied=248 written=280 -> Bitmap Heap Scan on orders (cost=96908.71..419828.84 rows=4576275 width=12) (actual time=4989.608..21532.848 rows=4557297 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=180835 read=85898 dirtied=248 written=244 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..95764.65 rows=4576275 width=0) (actual time=4868.867..4868.867 rows=4575464 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=742 read=11715 written=208 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=5057.103..5057.103 rows=300270 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10557kB Buffers: shared hit=145372 read=866 written=36 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=74.347..4841.446 rows=300270 loops=1) Buffers: shared hit=145372 read=866 written=36 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.042..0.123 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..0.028 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=0.016..0.018 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=55.857..946.352 rows=60054 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=145370 read=866 written=36 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=44.564..44.564 rows=60054 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=5 read=831 written=36 -> Index Scan using pk_supplier on supplier (cost=0.00..0.28 rows=1 width=8) (actual time=0.075..0.075 rows=1 loops=24340) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=73146 -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) (actual time=0.071..0.072 rows=1 loops=24340) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=48680 Total runtime: 71015.649 ms (64 rows) COMMIT; COMMIT