BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'INDIA' 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 = 'ASIA' and s_nationkey = n2.n_nationkey and o_orderdate between date '1995-01-01' and date '1996-12-31' and p_type = 'MEDIUM BURNISHED STEEL' ) as all_nations group by o_year order by o_year; QUERY PLAN ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1767967.58..1767969.40 rows=729 width=38) (actual time=11637.267..11637.267 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=2012621 read=305448 dirtied=1862 written=449 -> HashAggregate (cost=1767920.16..1767932.92 rows=729 width=38) (actual time=11637.200..11637.201 rows=2 loops=1) Group Key: date_part('year'::text, (orders.o_orderdate)::timestamp without time zone) Buffers: shared hit=2012618 read=305448 dirtied=1862 written=449 -> Hash Join (cost=39455.78..1767419.98 rows=25009 width=38) (actual time=1192.158..11596.776 rows=24579 loops=1) Hash Cond: (supplier.s_nationkey = n2.n_nationkey) Buffers: shared hit=2012618 read=305448 dirtied=1862 written=449 -> Nested Loop (cost=39454.22..1766949.50 rows=25009 width=16) (actual time=1192.101..11562.882 rows=24579 loops=1) Buffers: shared hit=2012614 read=305448 dirtied=1862 written=449 -> Hash Join (cost=39453.92..1758880.04 rows=25009 width=16) (actual time=1192.076..11371.255 rows=24579 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=1938735 read=305448 dirtied=1862 written=449 -> Nested Loop (cost=423.24..1719130.34 rows=125046 width=20) (actual time=7.451..10105.925 rows=122806 loops=1) Buffers: shared hit=1828603 read=269343 dirtied=1862 written=383 -> Nested Loop (cost=422.80..1516819.12 rows=413170 width=16) (actual time=7.362..4184.108 rows=405097 loops=1) Buffers: shared hit=277960 read=197417 dirtied=1707 written=280 -> Bitmap Heap Scan on part (cost=422.24..28508.60 rows=13653 width=4) (actual time=7.284..174.521 rows=13527 loops=1) Recheck Cond: ((p_type)::text = 'MEDIUM BURNISHED STEEL'::text) Heap Blocks: exact=11585 Buffers: shared hit=2166 read=9503 written=10 -> Bitmap Index Scan on part_p_type_p_partkey_idx (cost=0.00..418.82 rows=13653 width=0) (actual time=5.019..5.019 rows=13527 loops=1) Index Cond: ((p_type)::text = 'MEDIUM BURNISHED STEEL'::text) Buffers: shared read=84 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.56..108.70 rows=31 width=20) (actual time=0.028..0.286 rows=30 loops=13527) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=275794 read=187914 dirtied=1707 written=270 -> Index Scan using pk_orders on orders (cost=0.43..0.48 rows=1 width=12) (actual time=0.014..0.014 rows=0 loops=405097) 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=1550643 read=71926 dirtied=155 written=103 -> Hash (cost=35280.69..35280.69 rows=300000 width=4) (actual time=1180.302..1180.302 rows=300270 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 14653kB Buffers: shared hit=110132 read=36105 written=66 -> Nested Loop (cost=906.18..35280.69 rows=300000 width=4) (actual time=20.934..1074.546 rows=300270 loops=1) Buffers: shared hit=110132 read=36105 written=66 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.040..0.068 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..0.014 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.016..0.016 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=0.010..0.010 rows=1 loops=1) Filter: (r_name = 'ASIA'::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=18.550..204.022 rows=60054 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Heap Blocks: exact=145400 Buffers: shared hit=110130 read=36105 written=66 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=12.156..12.156 rows=60054 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=5 read=830 written=1 -> Index Scan using pk_supplier on supplier (cost=0.29..0.31 rows=1 width=8) (actual time=0.006..0.007 rows=1 loops=24579) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=73879 -> 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=0.004..0.006 rows=25 loops=1) Buffers: shared hit=1 Planning time: 8.041 ms Execution time: 11637.985 ms (68 rows) COMMIT; COMMIT