BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'MOZAMBIQUE' 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 = 'AFRICA' and s_nationkey = n2.n_nationkey and o_orderdate between date '1995-01-01' and date '1996-12-31' and p_type = 'STANDARD POLISHED BRASS' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2194136.64..2194138.47 rows=733 width=38) (actual time=24293.729..24293.729 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=775030 read=231816 dirtied=2868 written=248 -> HashAggregate (cost=2194088.93..2194101.76 rows=733 width=38) (actual time=24293.669..24293.671 rows=2 loops=1) Buffers: shared hit=775027 read=231816 dirtied=2868 written=248 -> Nested Loop (cost=501728.79..2193592.71 rows=24811 width=38) (actual time=18730.712..24250.919 rows=24283 loops=1) Buffers: shared hit=775027 read=231816 dirtied=2868 written=248 -> Nested Loop (cost=501728.79..2186516.61 rows=24811 width=16) (actual time=18730.644..24151.992 rows=24283 loops=1) Buffers: shared hit=726461 read=231816 dirtied=2868 written=248 -> Hash Join (cost=501728.79..2179283.44 rows=24839 width=16) (actual time=18730.580..23924.022 rows=24283 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=653479 read=231816 dirtied=2868 written=248 -> Nested Loop (cost=0.00..1675266.58 rows=407935 width=16) (actual time=0.308..4206.530 rows=400566 loops=1) Buffers: shared hit=252617 read=217846 dirtied=2808 written=248 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..46779.66 rows=13480 width=4) (actual time=0.275..164.228 rows=13334 loops=1) Index Cond: (p_type = 'STANDARD POLISHED BRASS'::text) Heap Fetches: 13334 Buffers: shared hit=1 read=11460 written=13 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.50 rows=31 width=20) (actual time=0.029..0.293 rows=30 loops=13334) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=252616 read=206386 dirtied=2808 written=235 -> Hash (cost=490209.38..490209.38 rows=921553 width=8) (actual time=18729.450..18729.450 rows=911872 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35620kB Buffers: shared hit=400859 read=13970 dirtied=60 -> Hash Join (cost=139050.22..490209.38 rows=921553 width=8) (actual time=3951.558..18126.712 rows=911872 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=400859 read=13970 dirtied=60 -> Bitmap Heap Scan on orders (cost=100019.60..424684.10 rows=4607767 width=12) (actual time=3068.523..6470.597 rows=4561632 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=255536 read=13144 dirtied=60 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..98867.65 rows=4607767 width=0) (actual time=2926.708..2926.708 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=882.329..882.329 rows=299493 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10530kB Buffers: shared hit=145323 read=826 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=22.788..783.291 rows=299493 loops=1) Buffers: shared hit=145323 read=826 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.023..0.064 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..0.015 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.011..0.011 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..0.010 rows=1 loops=1) Filter: (r_name = 'AFRICA'::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=21.476..143.585 rows=59899 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=145321 read=826 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=14.428..14.428 rows=59899 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=7 read=826 -> Index Scan using pk_supplier on supplier (cost=0.00..0.28 rows=1 width=8) (actual time=0.008..0.008 rows=1 loops=24283) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=72982 -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) (actual time=0.002..0.002 rows=1 loops=24283) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=48566 Total runtime: 24303.083 ms (64 rows) COMMIT; COMMIT