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 = 'ECONOMY ANODIZED STEEL' ) as all_nations group by o_year order by o_year; QUERY PLAN ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1808317.44..1808319.27 rows=730 width=38) (actual time=15544.775..15544.776 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=1885454 read=420991 dirtied=422 written=7734 -> HashAggregate (cost=1808269.95..1808282.73 rows=730 width=38) (actual time=15544.709..15544.709 rows=2 loops=1) Group Key: date_part('year'::text, (orders.o_orderdate)::timestamp without time zone) Buffers: shared hit=1885451 read=420991 dirtied=422 written=7734 -> Hash Join (cost=39466.93..1807758.87 rows=25554 width=38) (actual time=1470.410..15493.925 rows=24256 loops=1) Hash Cond: (supplier.s_nationkey = n2.n_nationkey) Buffers: shared hit=1885451 read=420991 dirtied=422 written=7734 -> Nested Loop (cost=39465.37..1807278.17 rows=25554 width=16) (actual time=1470.332..15445.258 rows=24256 loops=1) Buffers: shared hit=1885447 read=420991 dirtied=422 written=7734 -> Hash Join (cost=39465.08..1799024.44 rows=25580 width=16) (actual time=1470.293..15223.497 rows=24256 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=1812705 read=420838 dirtied=422 written=7734 -> Nested Loop (cost=434.39..1759258.32 rows=127901 width=20) (actual time=13.701..13628.904 rows=122397 loops=1) Buffers: shared hit=1679605 read=408001 dirtied=422 written=7734 -> Nested Loop (cost=433.96..1552574.92 rows=422118 width=16) (actual time=12.904..5874.062 rows=403464 loops=1) Buffers: shared hit=213882 read=257622 dirtied=422 written=4644 -> Bitmap Heap Scan on part (cost=433.39..28990.61 rows=14060 width=4) (actual time=12.784..121.239 rows=13452 loops=1) Recheck Cond: ((p_type)::text = 'ECONOMY ANODIZED STEEL'::text) Heap Blocks: exact=11517 Buffers: shared hit=7356 read=4246 written=109 -> Bitmap Index Scan on part_p_type_p_partkey_idx (cost=0.00..429.88 rows=14060 width=0) (actual time=9.183..9.183 rows=13452 loops=1) Index Cond: ((p_type)::text = 'ECONOMY ANODIZED STEEL'::text) Buffers: shared read=85 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.56..108.05 rows=31 width=20) (actual time=0.036..0.415 rows=30 loops=13452) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=206526 read=253376 dirtied=422 written=4535 -> Index Scan using pk_orders on orders (cost=0.43..0.48 rows=1 width=12) (actual time=0.018..0.018 rows=0 loops=403464) 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=1465723 read=150379 written=3090 -> Hash (cost=35280.69..35280.69 rows=300000 width=4) (actual time=1450.705..1450.705 rows=299436 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 14624kB Buffers: shared hit=133100 read=12837 -> Nested Loop (cost=906.18..35280.69 rows=300000 width=4) (actual time=32.341..1324.818 rows=299436 loops=1) Buffers: shared hit=133100 read=12837 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.069..0.135 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=0.022..0.022 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=0.014..0.015 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=23.269..250.872 rows=59887 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Heap Blocks: exact=145102 Buffers: shared hit=133098 read=12837 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=15.639..15.639 rows=59887 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=7 read=826 -> Index Scan using pk_supplier on supplier (cost=0.29..0.31 rows=1 width=8) (actual time=0.007..0.008 rows=1 loops=24256) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=72742 read=153 -> Hash (cost=1.25..1.25 rows=25 width=30) (actual time=0.029..0.029 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=0.008..0.011 rows=25 loops=1) Buffers: shared hit=1 Planning time: 6.888 ms Execution time: 15546.193 ms (68 rows) COMMIT; COMMIT