BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'IRAQ' 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 BRUSHED STEEL' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2177166.84..2177168.66 rows=728 width=38) (actual time=50775.263..50775.263 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=768015 read=234159 dirtied=399 -> HashAggregate (cost=2177119.49..2177132.23 rows=728 width=38) (actual time=50775.167..50775.169 rows=2 loops=1) Buffers: shared hit=768012 read=234159 dirtied=399 -> Nested Loop (cost=495478.00..2176632.19 rows=24365 width=38) (actual time=33368.543..50683.328 rows=23876 loops=1) Buffers: shared hit=768012 read=234159 dirtied=399 -> Nested Loop (cost=495478.00..2169683.29 rows=24365 width=16) (actual time=33368.451..50265.151 rows=23876 loops=1) Buffers: shared hit=720260 read=234159 dirtied=399 -> Hash Join (cost=495478.00..2162585.80 rows=24373 width=16) (actual time=33368.400..49254.950 rows=23876 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=648509 read=234159 dirtied=399 -> Nested Loop (cost=0.00..1664847.59 rows=403297 width=16) (actual time=0.480..14429.050 rows=401410 loops=1) Buffers: shared hit=266743 read=203028 dirtied=399 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..46522.58 rows=13393 width=4) (actual time=0.377..521.594 rows=13374 loops=1) Index Cond: (p_type = 'LARGE BRUSHED STEEL'::text) Heap Fetches: 13374 Buffers: shared hit=3039 read=8523 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.52 rows=31 width=20) (actual time=0.119..1.022 rows=30 loops=13374) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=263704 read=194505 dirtied=399 -> Hash (cost=484101.25..484101.25 rows=910140 width=8) (actual time=33366.209..33366.209 rows=911525 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35607kB Buffers: shared hit=381763 read=31131 -> Hash Join (cost=135393.20..484101.25 rows=910140 width=8) (actual time=8688.145..32734.563 rows=911525 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=381763 read=31131 -> Bitmap Heap Scan on orders (cost=96362.58..418904.10 rows=4550701 width=12) (actual time=4581.648..14358.423 rows=4561773 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=249800 read=16938 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..95224.91 rows=4550701 width=0) (actual time=4451.923..4451.923 rows=4575464 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared read=12457 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=4106.119..4106.119 rows=299838 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10542kB Buffers: shared hit=131963 read=14193 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=45.716..3835.980 rows=299838 loops=1) Buffers: shared hit=131963 read=14193 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.063..0.122 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=0.010..0.029 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.037..0.037 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=0.033..0.034 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=46.629..744.583 rows=59968 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=131961 read=14193 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=33.798..33.798 rows=59968 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=5 read=832 -> Index Scan using pk_supplier on supplier (cost=0.00..0.28 rows=1 width=8) (actual time=0.039..0.040 rows=1 loops=23876) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=71751 -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) (actual time=0.013..0.014 rows=1 loops=23876) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=47752 Total runtime: 50796.160 ms (64 rows) COMMIT; COMMIT