BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'KENYA' 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 = 'SMALL BURNISHED COPPER' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2185363.20..2185365.03 rows=733 width=38) (actual time=31851.063..31851.064 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=800087 read=193693 dirtied=555 written=8962 -> HashAggregate (cost=2185315.49..2185328.31 rows=733 width=38) (actual time=31850.972..31850.975 rows=2 loops=1) Buffers: shared hit=800084 read=193693 dirtied=555 written=8962 -> Nested Loop (cost=495659.41..2184823.19 rows=24615 width=38) (actual time=25442.706..31792.784 rows=23944 loops=1) Buffers: shared hit=800084 read=193693 dirtied=555 written=8962 -> Nested Loop (cost=495659.41..2177802.99 rows=24615 width=16) (actual time=25442.658..31637.271 rows=23944 loops=1) Buffers: shared hit=752196 read=193693 dirtied=555 written=8962 -> Hash Join (cost=495659.41..2170635.01 rows=24615 width=16) (actual time=25442.620..31327.136 rows=23944 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=680239 read=193689 dirtied=555 written=8962 -> Nested Loop (cost=0.00..1672706.98 rows=404496 width=16) (actual time=1.397..4589.978 rows=395114 loops=1) Buffers: shared hit=363184 read=98614 dirtied=555 written=5346 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..46759.81 rows=13473 width=4) (actual time=0.442..234.715 rows=13149 loops=1) Index Cond: (p_type = 'SMALL BURNISHED COPPER'::text) Heap Fetches: 13149 Buffers: shared hit=1256 read=9996 written=494 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.37 rows=31 width=20) (actual time=0.040..0.318 rows=30 loops=13149) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=361928 read=88618 dirtied=555 written=4852 -> Hash (cost=484238.14..484238.14 rows=913701 width=8) (actual time=25439.876..25439.876 rows=911011 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35587kB Buffers: shared hit=317052 read=95075 written=3616 -> Hash Join (cost=135919.68..484238.14 rows=913701 width=8) (actual time=5620.424..24416.378 rows=911011 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=317052 read=95075 written=3616 -> Bitmap Heap Scan on orders (cost=96889.06..418938.62 rows=4568504 width=12) (actual time=3662.123..9452.586 rows=4557440 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=187139 read=78839 written=3616 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..95746.94 rows=4568504 width=0) (actual time=3509.207..3509.207 rows=4561961 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=4007 read=8449 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=1957.926..1957.926 rows=299493 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10530kB Buffers: shared hit=129913 read=16236 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=35.608..1790.719 rows=299493 loops=1) Buffers: shared hit=129913 read=16236 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.045..0.124 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..0.024 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 = '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=29.227..339.796 rows=59899 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=129911 read=16236 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=20.852..20.852 rows=59899 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=9 read=824 -> Index Scan using pk_supplier on supplier (cost=0.00..0.28 rows=1 width=8) (actual time=0.011..0.011 rows=1 loops=23944) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=71957 read=4 -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) (actual time=0.004..0.004 rows=1 loops=23944) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=47888 Total runtime: 31871.322 ms (64 rows) COMMIT; COMMIT