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 = 'LARGE BRUSHED BRASS' ) as all_nations group by o_year order by o_year; QUERY PLAN ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1693603.68..1693605.51 rows=729 width=38) (actual time=11399.499..11399.499 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=1734860 read=253410 dirtied=1317 written=216 -> HashAggregate (cost=1693556.26..1693569.02 rows=729 width=38) (actual time=11399.437..11399.438 rows=2 loops=1) Group Key: date_part('year'::text, (orders.o_orderdate)::timestamp without time zone) Buffers: shared hit=1734857 read=253410 dirtied=1317 written=216 -> Hash Join (cost=39434.51..1693080.80 rows=23773 width=38) (actual time=1167.181..11359.189 rows=24062 loops=1) Hash Cond: (supplier.s_nationkey = n2.n_nationkey) Buffers: shared hit=1734857 read=253410 dirtied=1317 written=216 -> Nested Loop (cost=39432.95..1692633.50 rows=23773 width=16) (actual time=1167.123..11321.023 rows=24062 loops=1) Buffers: shared hit=1734853 read=253410 dirtied=1317 written=216 -> Hash Join (cost=39432.65..1684962.85 rows=23773 width=16) (actual time=1167.098..11089.171 rows=24062 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=1662529 read=253410 dirtied=1317 written=216 -> Nested Loop (cost=401.97..1645248.68 rows=118866 width=20) (actual time=7.272..9812.562 rows=120098 loops=1) Buffers: shared hit=1552482 read=217309 dirtied=1317 written=194 -> Nested Loop (cost=401.53..1453014.08 rows=392591 width=16) (actual time=6.946..4860.312 rows=395000 loops=1) Buffers: shared hit=267855 read=195398 dirtied=1317 written=180 -> Bitmap Heap Scan on part (cost=400.97..27670.77 rows=12973 width=4) (actual time=6.888..205.708 rows=13184 loops=1) Recheck Cond: ((p_type)::text = 'LARGE BRUSHED BRASS'::text) Heap Blocks: exact=11282 Buffers: shared hit=59 read=11291 written=16 -> Bitmap Index Scan on part_p_type_p_partkey_idx (cost=0.00..397.73 rows=12973 width=0) (actual time=4.576..4.576 rows=13184 loops=1) Index Cond: ((p_type)::text = 'LARGE BRUSHED BRASS'::text) Buffers: shared read=68 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.56..109.56 rows=31 width=20) (actual time=0.032..0.343 rows=30 loops=13184) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=267796 read=184107 dirtied=1317 written=164 -> Index Scan using orders_o_orderkey_o_orderdate_idx on orders (cost=0.43..0.48 rows=1 width=12) (actual time=0.012..0.012 rows=0 loops=395000) Index Cond: ((o_orderkey = lineitem.l_orderkey) AND (o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=1284627 read=21911 written=14 -> Hash (cost=35280.69..35280.69 rows=300000 width=4) (actual time=1156.404..1156.404 rows=299493 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 14626kB Buffers: shared hit=110047 read=36101 written=22 -> Nested Loop (cost=906.18..35280.69 rows=300000 width=4) (actual time=23.076..1052.060 rows=299493 loops=1) Buffers: shared hit=110047 read=36101 written=22 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.075..0.161 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..0.016 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.046..0.046 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=0.036..0.038 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=19.132..199.419 rows=59899 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Heap Blocks: exact=145314 Buffers: shared hit=110045 read=36101 written=22 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=12.598..12.598 rows=59899 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=7 read=825 written=2 -> Index Scan using pk_supplier on supplier (cost=0.29..0.31 rows=1 width=8) (actual time=0.008..0.009 rows=1 loops=24062) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=72324 -> Hash (cost=1.25..1.25 rows=25 width=30) (actual time=0.022..0.022 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=0.005..0.009 rows=25 loops=1) Buffers: shared hit=1 Planning time: 8.602 ms Execution time: 11400.542 ms (66 rows) COMMIT; COMMIT