BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'UNITED STATES' 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 = 'AMERICA' and s_nationkey = n2.n_nationkey and o_orderdate between date '1995-01-01' and date '1996-12-31' and p_type = 'LARGE ANODIZED STEEL' ) as all_nations group by o_year order by o_year; QUERY PLAN ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1736146.67..1736148.50 rows=729 width=38) (actual time=10973.909..10973.910 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=1983826 read=302089 dirtied=2146 written=1795 -> HashAggregate (cost=1736099.25..1736112.01 rows=729 width=38) (actual time=10973.840..10973.841 rows=2 loops=1) Group Key: date_part('year'::text, (orders.o_orderdate)::timestamp without time zone) Buffers: shared hit=1983823 read=302089 dirtied=2146 written=1795 -> Hash Join (cost=39445.45..1735609.07 rows=24509 width=38) (actual time=841.454..10935.523 rows=24270 loops=1) Hash Cond: (supplier.s_nationkey = n2.n_nationkey) Buffers: shared hit=1983823 read=302089 dirtied=2146 written=1795 -> Nested Loop (cost=39443.89..1735147.97 rows=24509 width=16) (actual time=841.402..10902.543 rows=24270 loops=1) Buffers: shared hit=1983819 read=302089 dirtied=2146 written=1795 -> Hash Join (cost=39443.60..1727239.85 rows=24509 width=16) (actual time=841.383..10720.354 rows=24270 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=1910883 read=302089 dirtied=2146 written=1795 -> Nested Loop (cost=412.91..1687504.53 rows=122543 width=20) (actual time=7.561..9813.135 rows=121004 loops=1) Buffers: shared hit=1769993 read=297042 dirtied=2146 written=1437 -> Nested Loop (cost=412.48..1489241.67 rows=404898 width=16) (actual time=7.434..4208.494 rows=399103 loops=1) Buffers: shared hit=240180 read=228255 dirtied=1877 written=1048 -> Bitmap Heap Scan on part (cost=411.91..28143.64 rows=13353 width=4) (actual time=7.378..181.798 rows=13292 loops=1) Recheck Cond: ((p_type)::text = 'LARGE ANODIZED STEEL'::text) Heap Blocks: exact=11377 Buffers: shared hit=206 read=11254 written=54 -> Bitmap Index Scan on part_p_type_p_partkey_idx (cost=0.00..408.57 rows=13353 width=0) (actual time=5.125..5.125 rows=13292 loops=1) Index Cond: ((p_type)::text = 'LARGE ANODIZED STEEL'::text) Buffers: shared read=83 written=9 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.56..109.11 rows=31 width=20) (actual time=0.027..0.293 rows=30 loops=13292) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=239974 read=217001 dirtied=1877 written=994 -> Index Scan using pk_orders on orders (cost=0.43..0.48 rows=1 width=12) (actual time=0.013..0.013 rows=0 loops=399103) 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=1529813 read=68787 dirtied=269 written=389 -> Hash (cost=35280.69..35280.69 rows=300000 width=4) (actual time=829.979..829.979 rows=299436 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 14624kB Buffers: shared hit=140890 read=5047 written=358 -> Nested Loop (cost=906.18..35280.69 rows=300000 width=4) (actual time=20.433..743.644 rows=299436 loops=1) Buffers: shared hit=140890 read=5047 written=358 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.041..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=0.005..0.011 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.017..0.017 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..0.012 rows=1 loops=1) Filter: (r_name = 'AMERICA'::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=18.155..138.422 rows=59887 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Heap Blocks: exact=145102 Buffers: shared hit=140888 read=5047 written=358 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=11.795..11.795 rows=59887 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=7 read=826 written=39 -> 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=24270) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=72936 -> 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=0.003..0.006 rows=25 loops=1) Buffers: shared hit=1 Planning time: 7.521 ms Execution time: 10974.746 ms (68 rows) COMMIT; COMMIT