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 = 'LARGE BRUSHED STEEL' ) as all_nations group by o_year order by o_year; QUERY PLAN ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1720824.41..1720826.24 rows=732 width=38) (actual time=12055.803..12055.804 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=1751091 read=263220 -> HashAggregate (cost=1720776.77..1720789.58 rows=732 width=38) (actual time=12055.734..12055.735 rows=2 loops=1) Group Key: date_part('year'::text, (orders.o_orderdate)::timestamp without time zone) Buffers: shared hit=1751088 read=263220 -> Hash Join (cost=39449.10..1720291.11 rows=24283 width=38) (actual time=861.183..12007.748 rows=24418 loops=1) Hash Cond: (supplier.s_nationkey = n2.n_nationkey) Buffers: shared hit=1751088 read=263220 -> Nested Loop (cost=39447.53..1719834.24 rows=24283 width=16) (actual time=861.121..11961.040 rows=24418 loops=1) Buffers: shared hit=1751084 read=263220 -> Hash Join (cost=39447.24..1711999.01 rows=24283 width=16) (actual time=861.090..11727.252 rows=24418 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=1677677 read=263220 -> Nested Loop (cost=416.55..1672270.19 rows=121413 width=20) (actual time=7.693..10732.585 rows=121519 loops=1) Buffers: shared hit=1532269 read=262391 -> Nested Loop (cost=416.12..1476751.86 rows=399313 width=16) (actual time=7.528..5429.767 rows=400947 loops=1) Buffers: shared hit=241080 read=227819 -> Bitmap Heap Scan on part (cost=411.40..28063.46 rows=13287 width=4) (actual time=7.400..164.021 rows=13374 loops=1) Recheck Cond: ((p_type)::text = 'LARGE BRUSHED STEEL'::text) Heap Blocks: exact=11492 Buffers: shared hit=3537 read=8024 -> Bitmap Index Scan on part_p_type_p_partkey_idx (cost=0.00..408.08 rows=13287 width=0) (actual time=5.026..5.026 rows=13374 loops=1) Index Cond: ((p_type)::text = 'LARGE BRUSHED STEEL'::text) Buffers: shared read=69 -> Bitmap Heap Scan on lineitem (cost=4.72..108.72 rows=31 width=20) (actual time=0.044..0.381 rows=30 loops=13374) Recheck Cond: (l_partkey = part.p_partkey) Heap Blocks: exact=401779 Buffers: shared hit=237543 read=219795 -> Bitmap Index Scan on lineitem_l_partkey_l_quantity_l_shipmode_idx (cost=0.00..4.71 rows=31 width=0) (actual time=0.029..0.029 rows=30 loops=13374) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=39060 read=16499 -> Index Scan using orders_o_orderkey_o_orderdate_idx on orders (cost=0.43..0.48 rows=1 width=12) (actual time=0.012..0.012 rows=0 loops=400947) Index Cond: ((o_orderkey = lineitem.l_orderkey) AND (o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=1291189 read=34572 -> Hash (cost=35280.69..35280.69 rows=300000 width=4) (actual time=850.943..850.943 rows=300270 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 14653kB Buffers: shared hit=145408 read=829 -> Nested Loop (cost=906.18..35280.69 rows=300000 width=4) (actual time=22.926..759.746 rows=300270 loops=1) Buffers: shared hit=145408 read=829 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.061..0.091 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=0.007..0.016 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.023..0.023 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=0.016..0.017 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=20.385..140.766 rows=60054 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Heap Blocks: exact=145400 Buffers: shared hit=145406 read=829 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=13.276..13.276 rows=60054 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=7 read=828 -> Index Scan using pk_supplier on supplier (cost=0.29..0.31 rows=1 width=8) (actual time=0.008..0.008 rows=1 loops=24418) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=73407 -> 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..0.007 rows=25 loops=1) Buffers: shared hit=1 Planning time: 7.986 ms Execution time: 12056.757 ms (70 rows) COMMIT; COMMIT