BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'MOROCCO' 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 = 'LARGE BRUSHED BRASS' ) as all_nations group by o_year order by o_year; QUERY PLAN ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1725613.08..1725614.90 rows=729 width=38) (actual time=11922.930..11922.930 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=1911178 read=351006 dirtied=1251 written=3989 -> HashAggregate (cost=1725565.66..1725578.42 rows=729 width=38) (actual time=11922.877..11922.878 rows=2 loops=1) Group Key: date_part('year'::text, (orders.o_orderdate)::timestamp without time zone) Buffers: shared hit=1911175 read=351006 dirtied=1251 written=3989 -> Hash Join (cost=39444.83..1725080.44 rows=24261 width=38) (actual time=1227.670..11883.146 rows=24053 loops=1) Hash Cond: (supplier.s_nationkey = n2.n_nationkey) Buffers: shared hit=1911175 read=351006 dirtied=1251 written=3989 -> Nested Loop (cost=39443.27..1724623.98 rows=24261 width=16) (actual time=1227.615..11848.856 rows=24053 loops=1) Buffers: shared hit=1911171 read=351006 dirtied=1251 written=3989 -> Hash Join (cost=39442.98..1716795.87 rows=24261 width=16) (actual time=1227.596..11660.456 rows=24053 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=1838876 read=351006 dirtied=1251 written=3989 -> Nested Loop (cost=412.29..1677067.67 rows=121306 width=20) (actual time=7.248..10354.496 rows=119988 loops=1) Buffers: shared hit=1728829 read=314905 dirtied=1251 written=2148 -> Nested Loop (cost=411.86..1480817.50 rows=400812 width=16) (actual time=6.762..4217.275 rows=394619 loops=1) Buffers: shared hit=248293 read=214801 dirtied=1251 written=1252 -> Bitmap Heap Scan on part (cost=411.29..28047.06 rows=13273 width=4) (actual time=6.715..151.552 rows=13184 loops=1) Recheck Cond: ((p_type)::text = 'LARGE BRUSHED BRASS'::text) Heap Blocks: exact=11282 Buffers: shared hit=3478 read=7872 written=37 -> Bitmap Index Scan on part_p_type_p_partkey_idx (cost=0.00..407.98 rows=13273 width=0) (actual time=4.538..4.538 rows=13184 loops=1) Index Cond: ((p_type)::text = 'LARGE BRUSHED BRASS'::text) Buffers: shared read=68 written=3 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.56..109.14 rows=31 width=20) (actual time=0.029..0.298 rows=30 loops=13184) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=244815 read=206929 dirtied=1251 written=1215 -> Index Scan using pk_orders on orders (cost=0.43..0.48 rows=1 width=12) (actual time=0.015..0.015 rows=0 loops=394619) Index Cond: (o_orderkey = lineitem.l_orderkey) Filter: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Rows Removed by Filter: 1 Buffers: shared hit=1480536 read=100104 written=896 -> Hash (cost=35280.69..35280.69 rows=300000 width=4) (actual time=1216.145..1216.145 rows=299493 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 14626kB Buffers: shared hit=110047 read=36101 written=1841 -> Nested Loop (cost=906.18..35280.69 rows=300000 width=4) (actual time=21.159..1100.706 rows=299493 loops=1) Buffers: shared hit=110047 read=36101 written=1841 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.044..0.078 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=0.006..0.015 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.018..0.018 rows=1 loops=1) Buckets: 1024 Batches: 1 Memory Usage: 9kB Buffers: shared hit=1 -> Seq Scan on region (cost=0.00..1.06 rows=1 width=4) (actual time=0.010..0.012 rows=1 loops=1) Filter: (r_name = 'AFRICA'::bpchar) Rows Removed by Filter: 4 Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=905.11..6455.64 rows=60000 width=8) (actual time=18.927..208.996 rows=59899 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Heap Blocks: exact=145314 Buffers: shared hit=110045 read=36101 written=1841 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=12.514..12.514 rows=59899 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=7 read=825 written=45 -> Index Scan using pk_supplier on supplier (cost=0.29..0.31 rows=1 width=8) (actual time=0.006..0.007 rows=1 loops=24053) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=72295 -> Hash (cost=1.25..1.25 rows=25 width=30) (actual time=0.019..0.019 rows=25 loops=1) Buckets: 1024 Batches: 1 Memory Usage: 10kB Buffers: shared hit=1 -> Seq Scan on nation n2 (cost=0.00..1.25 rows=25 width=30) (actual time=0.004..0.006 rows=25 loops=1) Buffers: shared hit=1 Planning time: 8.332 ms Execution time: 11923.684 ms (68 rows) COMMIT; COMMIT