BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'VIETNAM' 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 = 'ECONOMY BRUSHED STEEL' ) as all_nations group by o_year order by o_year; QUERY PLAN ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1742261.70..1742263.52 rows=729 width=38) (actual time=7810.052..7810.053 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=1728254 read=291606 dirtied=61 written=16 -> HashAggregate (cost=1742214.28..1742227.04 rows=729 width=38) (actual time=7810.000..7810.000 rows=2 loops=1) Group Key: date_part('year'::text, (orders.o_orderdate)::timestamp without time zone) Buffers: shared hit=1728251 read=291606 dirtied=61 written=16 -> Hash Join (cost=39454.38..1741723.66 rows=24531 width=38) (actual time=857.930..7772.904 rows=24461 loops=1) Hash Cond: (supplier.s_nationkey = n2.n_nationkey) Buffers: shared hit=1728251 read=291606 dirtied=61 written=16 -> Nested Loop (cost=39452.82..1741262.14 rows=24531 width=16) (actual time=857.866..7741.632 rows=24461 loops=1) Buffers: shared hit=1728247 read=291606 dirtied=61 written=16 -> Hash Join (cost=39452.53..1733340.77 rows=24550 width=16) (actual time=857.854..7599.662 rows=24461 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=1654743 read=291606 dirtied=61 written=16 -> Nested Loop (cost=421.84..1693604.27 rows=122751 width=20) (actual time=6.341..6672.022 rows=122217 loops=1) Buffers: shared hit=1544611 read=255501 dirtied=61 written=16 -> Nested Loop (cost=421.41..1495048.34 rows=405510 width=16) (actual time=6.188..3619.504 rows=401937 loops=1) Buffers: shared hit=247279 read=223402 written=14 -> Bitmap Heap Scan on part (cost=416.69..28266.65 rows=13453 width=4) (actual time=6.098..142.255 rows=13411 loops=1) Recheck Cond: ((p_type)::text = 'ECONOMY BRUSHED STEEL'::text) Heap Blocks: exact=11429 Buffers: shared hit=1 read=11512 written=1 -> Bitmap Index Scan on part_p_type_p_partkey_idx (cost=0.00..413.32 rows=13453 width=0) (actual time=4.098..4.098 rows=13411 loops=1) Index Cond: ((p_type)::text = 'ECONOMY BRUSHED STEEL'::text) Buffers: shared read=84 -> Bitmap Heap Scan on lineitem (cost=4.72..108.72 rows=31 width=20) (actual time=0.033..0.249 rows=30 loops=13411) Recheck Cond: (l_partkey = part.p_partkey) Heap Blocks: exact=403538 Buffers: shared hit=247278 read=211890 written=13 -> Bitmap Index Scan on lineitem_l_partkey_l_quantity_l_shipmode_idx (cost=0.00..4.71 rows=31 width=0) (actual time=0.021..0.021 rows=30 loops=13411) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=39729 read=15901 written=1 -> Index Scan using orders_o_orderkey_o_orderdate_idx on orders (cost=0.43..0.48 rows=1 width=12) (actual time=0.007..0.007 rows=0 loops=401937) Index Cond: ((o_orderkey = lineitem.l_orderkey) AND (o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=1297332 read=32099 dirtied=61 written=2 -> Hash (cost=35280.69..35280.69 rows=300000 width=4) (actual time=848.473..848.473 rows=300270 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 14653kB Buffers: shared hit=110132 read=36105 -> Nested Loop (cost=906.18..35280.69 rows=300000 width=4) (actual time=17.656..765.029 rows=300270 loops=1) Buffers: shared hit=110132 read=36105 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.036..0.063 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=0.011..0.011 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=16.304..142.941 rows=60054 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Heap Blocks: exact=145400 Buffers: shared hit=110130 read=36105 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=10.576..10.576 rows=60054 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=5 read=830 -> Index Scan using pk_supplier on supplier (cost=0.29..0.31 rows=1 width=8) (actual time=0.004..0.005 rows=1 loops=24461) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=73504 -> 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=0.005..0.009 rows=25 loops=1) Buffers: shared hit=1 Planning time: 7.481 ms Execution time: 7810.807 ms (70 rows) COMMIT; COMMIT