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 = 'MEDIUM BRUSHED TIN' ) as all_nations group by o_year order by o_year; QUERY PLAN ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1754950.39..1754952.21 rows=729 width=38) (actual time=12515.592..12515.592 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=2091841 read=268346 -> HashAggregate (cost=1754902.97..1754915.73 rows=729 width=38) (actual time=12515.553..12515.555 rows=2 loops=1) Group Key: date_part('year'::text, (orders.o_orderdate)::timestamp without time zone) Buffers: shared hit=2091838 read=268346 -> Hash Join (cost=38758.66..1754408.33 rows=24732 width=38) (actual time=1992.532..12472.478 rows=24899 loops=1) Hash Cond: (supplier.s_nationkey = n2.n_nationkey) Buffers: shared hit=2091838 read=268346 -> Nested Loop (cost=38757.09..1753943.04 rows=24732 width=16) (actual time=1992.484..12429.209 rows=24899 loops=1) Buffers: shared hit=2091834 read=268346 -> Hash Join (cost=38756.80..1745949.72 rows=24773 width=16) (actual time=1992.473..12278.270 rows=24899 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=2017000 read=268346 -> Nested Loop (cost=426.65..1706907.35 rows=123864 width=20) (actual time=7.104..10197.232 rows=123841 loops=1) Buffers: shared hit=1840603 read=268345 -> Nested Loop (cost=426.22..1506668.07 rows=408948 width=16) (actual time=6.960..5731.117 rows=407615 loops=1) Buffers: shared hit=256022 read=220250 -> Bitmap Heap Scan on part (cost=421.57..28406.89 rows=13567 width=4) (actual time=6.863..178.054 rows=13597 loops=1) Recheck Cond: ((p_type)::text = 'MEDIUM BRUSHED TIN'::text) Heap Blocks: exact=11579 Buffers: shared hit=337 read=11312 -> Bitmap Index Scan on part_p_type_p_partkey_idx (cost=0.00..418.18 rows=13567 width=0) (actual time=4.516..4.516 rows=13597 loops=1) Index Cond: ((p_type)::text = 'MEDIUM BRUSHED TIN'::text) Buffers: shared read=70 -> Bitmap Heap Scan on lineitem (cost=4.65..108.65 rows=31 width=20) (actual time=0.042..0.393 rows=30 loops=13597) Recheck Cond: (l_partkey = part.p_partkey) Heap Blocks: exact=409112 Buffers: shared hit=255685 read=208938 -> Bitmap Index Scan on lineitem_l_partkey_l_quantity_idx (cost=0.00..4.64 rows=31 width=0) (actual time=0.023..0.023 rows=30 loops=13597) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=42461 read=13050 -> Index Scan using pk_orders on orders (cost=0.43..0.48 rows=1 width=12) (actual time=0.010..0.010 rows=0 loops=407615) 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=1584581 read=48095 -> Hash (cost=34580.15..34580.15 rows=300000 width=4) (actual time=1982.676..1982.676 rows=299838 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 14638kB Buffers: shared hit=176397 read=1 -> Nested Loop (cost=766.08..34580.15 rows=300000 width=4) (actual time=3.702..1892.045 rows=299838 loops=1) Buffers: shared hit=176397 read=1 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.033..0.054 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..0.012 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.013..0.013 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=0.009..0.009 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=765.00..6315.54 rows=60000 width=8) (actual time=3.625..369.190 rows=59968 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Rows Removed by Index Recheck: 1440032 Heap Blocks: lossy=176390 Buffers: shared hit=176395 read=1 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_brin_idx (cost=0.00..750.00 rows=60000 width=0) (actual time=3.593..3.593 rows=353280 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=5 read=1 -> Index Scan using pk_supplier on supplier (cost=0.29..0.31 rows=1 width=8) (actual time=0.005..0.005 rows=1 loops=24899) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=74834 -> Hash (cost=1.25..1.25 rows=25 width=30) (actual time=0.018..0.018 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=0.002..0.007 rows=25 loops=1) Buffers: shared hit=1 Planning time: 6.499 ms Execution time: 12516.402 ms (73 rows) COMMIT; COMMIT