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 = 'PROMO ANODIZED BRASS' ) as all_nations group by o_year order by o_year; QUERY PLAN ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1766591.84..1766593.67 rows=729 width=38) (actual time=14829.302..14829.302 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=1886072 read=387363 dirtied=393 written=8775 -> HashAggregate (cost=1766544.42..1766557.18 rows=729 width=38) (actual time=14829.235..14829.237 rows=2 loops=1) Group Key: date_part('year'::text, (orders.o_orderdate)::timestamp without time zone) Buffers: shared hit=1886069 read=387363 dirtied=393 written=8775 -> Hash Join (cost=39455.93..1766047.46 rows=24848 width=38) (actual time=1499.149..14778.491 rows=24061 loops=1) Hash Cond: (supplier.s_nationkey = n2.n_nationkey) Buffers: shared hit=1886069 read=387363 dirtied=393 written=8775 -> Nested Loop (cost=39454.37..1765580.00 rows=24848 width=16) (actual time=1499.079..14730.603 rows=24061 loops=1) Buffers: shared hit=1886065 read=387363 dirtied=393 written=8775 -> Hash Join (cost=39454.08..1757562.46 rows=24848 width=16) (actual time=1499.032..14513.061 rows=24061 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=1813916 read=387185 dirtied=393 written=8775 -> Nested Loop (cost=423.39..1717817.40 rows=124239 width=20) (actual time=7.707..12887.553 rows=120406 loops=1) Buffers: shared hit=1679835 read=375118 dirtied=393 written=8775 -> Nested Loop (cost=422.96..1516821.17 rows=410503 width=16) (actual time=7.403..5398.764 rows=397158 loops=1) Buffers: shared hit=227963 read=236182 dirtied=393 written=5557 -> Bitmap Heap Scan on part (cost=422.39..28532.74 rows=13673 width=4) (actual time=7.298..102.712 rows=13249 loops=1) Recheck Cond: ((p_type)::text = 'PROMO ANODIZED BRASS'::text) Heap Blocks: exact=11325 Buffers: shared hit=8867 read=2541 written=103 -> Bitmap Index Scan on part_p_type_p_partkey_idx (cost=0.00..418.98 rows=13673 width=0) (actual time=4.815..4.815 rows=13249 loops=1) Index Cond: ((p_type)::text = 'PROMO ANODIZED BRASS'::text) Buffers: shared read=83 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.56..108.54 rows=31 width=20) (actual time=0.034..0.388 rows=30 loops=13249) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=219096 read=233641 dirtied=393 written=5454 -> Index Scan using pk_orders on orders (cost=0.43..0.48 rows=1 width=12) (actual time=0.018..0.018 rows=0 loops=397158) 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=1451872 read=138936 written=3218 -> Hash (cost=35280.69..35280.69 rows=300000 width=4) (actual time=1487.498..1487.498 rows=299493 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 14626kB Buffers: shared hit=134081 read=12067 -> Nested Loop (cost=906.18..35280.69 rows=300000 width=4) (actual time=31.714..1334.341 rows=299493 loops=1) Buffers: shared hit=134081 read=12067 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.045..0.113 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..0.018 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.019..0.019 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=0.012..0.014 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=28.709..251.302 rows=59899 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Heap Blocks: exact=145314 Buffers: shared hit=134079 read=12067 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=19.184..19.184 rows=59899 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=9 read=823 -> Index Scan using pk_supplier on supplier (cost=0.29..0.31 rows=1 width=8) (actual time=0.007..0.008 rows=1 loops=24061) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=72149 read=178 -> Hash (cost=1.25..1.25 rows=25 width=30) (actual time=0.021..0.021 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..0.007 rows=25 loops=1) Buffers: shared hit=1 Planning time: 9.528 ms Execution time: 14830.372 ms (68 rows) COMMIT; COMMIT