BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'CANADA' 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 = 'MEDIUM BURNISHED TIN' ) as all_nations group by o_year order by o_year; QUERY PLAN ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1731409.15..1731410.98 rows=729 width=38) (actual time=11104.624..11104.624 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=2034494 read=246036 dirtied=51 written=233 -> HashAggregate (cost=1731361.73..1731374.49 rows=729 width=38) (actual time=11104.559..11104.561 rows=2 loops=1) Group Key: date_part('year'::text, (orders.o_orderdate)::timestamp without time zone) Buffers: shared hit=2034491 read=246036 dirtied=51 written=233 -> Hash Join (cost=39449.66..1730872.27 rows=24473 width=38) (actual time=885.462..11065.543 rows=23789 loops=1) Hash Cond: (supplier.s_nationkey = n2.n_nationkey) Buffers: shared hit=2034491 read=246036 dirtied=51 written=233 -> Nested Loop (cost=39448.10..1730411.84 rows=24473 width=16) (actual time=885.405..11032.328 rows=23789 loops=1) Buffers: shared hit=2034487 read=246036 dirtied=51 written=233 -> Hash Join (cost=39447.81..1722515.33 rows=24473 width=16) (actual time=885.386..10844.196 rows=23789 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=1963020 read=246036 dirtied=51 written=233 -> Nested Loop (cost=417.12..1682781.05 rows=122363 width=20) (actual time=7.314..9892.470 rows=120606 loops=1) Buffers: shared hit=1823085 read=240034 dirtied=51 written=228 -> Nested Loop (cost=416.69..1484811.61 rows=404303 width=16) (actual time=7.183..4223.199 rows=398410 loops=1) Buffers: shared hit=289993 read=177320 dirtied=33 written=178 -> Bitmap Heap Scan on part (cost=411.97..28151.81 rows=13360 width=4) (actual time=7.064..168.214 rows=13268 loops=1) Recheck Cond: ((p_type)::text = 'MEDIUM BURNISHED TIN'::text) Heap Blocks: exact=11330 Buffers: shared hit=2259 read=9154 written=7 -> Bitmap Index Scan on part_p_type_p_partkey_idx (cost=0.00..408.63 rows=13360 width=0) (actual time=4.878..4.878 rows=13268 loops=1) Index Cond: ((p_type)::text = 'MEDIUM BURNISHED TIN'::text) Buffers: shared read=83 -> Bitmap Heap Scan on lineitem (cost=4.72..108.72 rows=31 width=20) (actual time=0.039..0.295 rows=30 loops=13268) Recheck Cond: (l_partkey = part.p_partkey) Heap Blocks: exact=400770 Buffers: shared hit=287734 read=168166 dirtied=33 written=171 -> Bitmap Index Scan on lineitem_l_partkey_l_quantity_l_shipmode_idx (cost=0.00..4.71 rows=31 width=0) (actual time=0.026..0.026 rows=30 loops=13268) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=40743 read=14387 written=14 -> 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=398410) 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=1533092 read=62714 dirtied=18 written=50 -> Hash (cost=35280.69..35280.69 rows=300000 width=4) (actual time=875.784..875.784 rows=299436 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 14624kB Buffers: shared hit=139935 read=6002 written=5 -> Nested Loop (cost=906.18..35280.69 rows=300000 width=4) (actual time=20.730..788.690 rows=299436 loops=1) Buffers: shared hit=139935 read=6002 written=5 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.040..0.070 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=0.017..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=0.011..0.013 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=18.683..147.264 rows=59887 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Heap Blocks: exact=145102 Buffers: shared hit=139933 read=6002 written=5 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=12.141..12.141 rows=59887 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=8 read=825 written=3 -> Index Scan using pk_supplier on supplier (cost=0.29..0.31 rows=1 width=8) (actual time=0.007..0.007 rows=1 loops=23789) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=71467 -> 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=0.004..0.007 rows=25 loops=1) Buffers: shared hit=1 Planning time: 8.515 ms Execution time: 11105.379 ms (72 rows) COMMIT; COMMIT