BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'ROMANIA' 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 = 'EUROPE' and s_nationkey = n2.n_nationkey and o_orderdate between date '1995-01-01' and date '1996-12-31' and p_type = 'STANDARD BURNISHED BRASS' ) as all_nations group by o_year order by o_year; QUERY PLAN ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1693922.10..1693923.93 rows=732 width=38) (actual time=11680.296..11680.297 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=1797161 read=214010 dirtied=1572 written=2605 -> HashAggregate (cost=1693874.47..1693887.28 rows=732 width=38) (actual time=11680.232..11680.232 rows=2 loops=1) Group Key: date_part('year'::text, (orders.o_orderdate)::timestamp without time zone) Buffers: shared hit=1797158 read=214010 dirtied=1572 written=2605 -> Hash Join (cost=39434.51..1693396.67 rows=23890 width=38) (actual time=875.724..11633.153 rows=24376 loops=1) Hash Cond: (supplier.s_nationkey = n2.n_nationkey) Buffers: shared hit=1797158 read=214010 dirtied=1572 written=2605 -> Nested Loop (cost=39432.95..1692947.17 rows=23890 width=16) (actual time=875.659..11587.331 rows=24376 loops=1) Buffers: shared hit=1797154 read=214010 dirtied=1572 written=2605 -> Hash Join (cost=39432.65..1685238.77 rows=23890 width=16) (actual time=875.636..11344.575 rows=24376 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=1723915 read=214010 dirtied=1572 written=2605 -> Nested Loop (cost=401.97..1645521.24 rows=119451 width=20) (actual time=8.263..10369.737 rows=121527 loops=1) Buffers: shared hit=1578707 read=213042 dirtied=1572 written=2543 -> Nested Loop (cost=401.53..1453159.75 rows=392861 width=16) (actual time=8.161..4845.645 rows=399790 loops=1) Buffers: shared hit=283088 read=186350 dirtied=1572 written=2241 -> Bitmap Heap Scan on part (cost=400.97..27670.77 rows=12973 width=4) (actual time=8.008..179.229 rows=13330 loops=1) Recheck Cond: ((p_type)::text = 'STANDARD BURNISHED BRASS'::text) Heap Blocks: exact=11299 Buffers: shared hit=2974 read=8408 written=145 -> Bitmap Index Scan on part_p_type_p_partkey_idx (cost=0.00..397.73 rows=12973 width=0) (actual time=5.654..5.654 rows=13330 loops=1) Index Cond: ((p_type)::text = 'STANDARD BURNISHED BRASS'::text) Buffers: shared read=83 written=6 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.56..109.57 rows=31 width=20) (actual time=0.033..0.337 rows=30 loops=13330) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=280114 read=177942 dirtied=1572 written=2096 -> Index Scan using orders_o_orderkey_o_orderdate_idx on orders (cost=0.43..0.48 rows=1 width=12) (actual time=0.013..0.013 rows=0 loops=399790) Index Cond: ((o_orderkey = lineitem.l_orderkey) AND (o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=1295619 read=26692 written=302 -> Hash (cost=35280.69..35280.69 rows=300000 width=4) (actual time=864.874..864.874 rows=300963 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 14677kB Buffers: shared hit=145208 read=968 written=62 -> Nested Loop (cost=906.18..35280.69 rows=300000 width=4) (actual time=23.943..774.119 rows=300963 loops=1) Buffers: shared hit=145208 read=968 written=62 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.050..0.084 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..0.013 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.024..0.024 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=0.019..0.020 rows=1 loops=1) Filter: (r_name = 'EUROPE'::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=21.644..143.723 rows=60193 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Heap Blocks: exact=145336 Buffers: shared hit=145206 read=968 written=62 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=14.290..14.290 rows=60193 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=7 read=831 written=55 -> Index Scan using pk_supplier on supplier (cost=0.29..0.31 rows=1 width=8) (actual time=0.008..0.009 rows=1 loops=24376) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=73239 -> Hash (cost=1.25..1.25 rows=25 width=30) (actual time=0.022..0.022 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..0.008 rows=25 loops=1) Buffers: shared hit=1 Planning time: 8.019 ms Execution time: 11681.402 ms (66 rows) COMMIT; COMMIT