BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'IRAN' 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 = 'MIDDLE EAST' and s_nationkey = n2.n_nationkey and o_orderdate between date '1995-01-01' and date '1996-12-31' and p_type = 'LARGE POLISHED STEEL' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2159015.67..2159017.50 rows=731 width=38) (actual time=29266.112..29266.113 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=822630 read=177402 dirtied=630 written=8547 -> HashAggregate (cost=2158968.11..2158980.90 rows=731 width=38) (actual time=29266.052..29266.054 rows=2 loops=1) Buffers: shared hit=822627 read=177402 dirtied=630 written=8547 -> Nested Loop (cost=495286.65..2158485.47 rows=24132 width=38) (actual time=22758.964..29204.924 rows=24120 loops=1) Buffers: shared hit=822627 read=177402 dirtied=630 written=8547 -> Nested Loop (cost=495286.65..2151603.02 rows=24132 width=16) (actual time=22758.871..29034.845 rows=24120 loops=1) Buffers: shared hit=774387 read=177402 dirtied=630 written=8547 -> Hash Join (cost=495286.65..2144575.70 rows=24132 width=16) (actual time=22758.807..28715.791 rows=24120 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=701915 read=177400 dirtied=630 written=8547 -> Nested Loop (cost=0.00..1647061.28 rows=397291 width=16) (actual time=0.445..4638.358 rows=399709 loops=1) Buffers: shared hit=368815 read=98363 dirtied=630 written=4663 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..46043.58 rows=13233 width=4) (actual time=0.261..272.882 rows=13309 loops=1) Index Cond: (p_type = 'LARGE POLISHED STEEL'::text) Heap Fetches: 13309 Buffers: shared hit=103 read=11358 written=515 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.68 rows=31 width=20) (actual time=0.042..0.313 rows=30 loops=13309) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=368712 read=87005 dirtied=630 written=4148 -> Hash (cost=483886.33..483886.33 rows=912025 width=8) (actual time=22756.920..22756.920 rows=910630 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35572kB Buffers: shared hit=333097 read=79037 written=3884 -> Hash Join (cost=135741.78..483886.33 rows=912025 width=8) (actual time=5126.551..21628.667 rows=910630 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=333097 read=79037 written=3884 -> Bitmap Heap Scan on orders (cost=96711.16..418635.00 rows=4560123 width=12) (actual time=3194.552..7685.730 rows=4557440 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=200707 read=65271 written=3884 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..95571.13 rows=4560123 width=0) (actual time=3058.775..3058.775 rows=4561961 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=8121 read=4335 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=1931.574..1931.574 rows=299838 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10542kB Buffers: shared hit=132390 read=13766 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=37.348..1751.919 rows=299838 loops=1) Buffers: shared hit=132390 read=13766 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.079..0.150 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=0.013..0.028 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.034..0.034 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=0.028..0.030 rows=1 loops=1) Filter: (r_name = 'MIDDLE EAST'::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=33.024..331.502 rows=59968 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=132388 read=13766 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=22.976..22.976 rows=59968 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=11 read=826 -> 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=24120) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=72472 read=2 -> 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=24120) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=48240 Total runtime: 29295.728 ms (64 rows) COMMIT; COMMIT