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 = 'SMALL POLISHED NICKEL' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2218436.58..2218438.40 rows=731 width=38) (actual time=28326.579..28326.579 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=794988 read=215713 dirtied=359 -> HashAggregate (cost=2218389.01..2218401.80 rows=731 width=38) (actual time=28326.506..28326.507 rows=2 loops=1) Buffers: shared hit=794985 read=215713 dirtied=359 -> Nested Loop (cost=496398.52..2217885.65 rows=25168 width=38) (actual time=21128.940..28264.413 rows=24633 loops=1) Buffers: shared hit=794985 read=215713 dirtied=359 -> Nested Loop (cost=496398.52..2210707.74 rows=25168 width=16) (actual time=21128.852..28102.250 rows=24633 loops=1) Buffers: shared hit=745719 read=215713 dirtied=359 -> Hash Join (cost=496398.52..2203378.74 rows=25168 width=16) (actual time=21128.808..27790.173 rows=24633 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=671685 read=215713 dirtied=359 -> Nested Loop (cost=0.00..1704655.72 rows=414563 width=16) (actual time=0.466..5460.432 rows=405510 loops=1) Buffers: shared hit=273839 read=200580 dirtied=359 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..47633.26 rows=13767 width=4) (actual time=0.350..184.188 rows=13501 loops=1) Index Cond: (p_type = 'SMALL POLISHED NICKEL'::text) Heap Fetches: 13501 Buffers: shared hit=3093 read=8478 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.05 rows=31 width=20) (actual time=0.038..0.376 rows=30 loops=13501) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=270746 read=192102 dirtied=359 -> Hash (cost=484970.08..484970.08 rows=914275 width=8) (actual time=21126.508..21126.508 rows=913295 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35676kB Buffers: shared hit=397843 read=15133 -> Hash Join (cost=135833.09..484970.08 rows=914275 width=8) (actual time=4664.900..20597.976 rows=913295 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=397843 read=15133 -> Bitmap Heap Scan on orders (cost=96802.47..419654.06 rows=4571373 width=12) (actual time=3267.626..7453.945 rows=4561773 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=252436 read=14302 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..95659.63 rows=4571373 width=0) (actual time=3077.635..3077.635 rows=4575464 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared read=12457 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=1396.753..1396.753 rows=300270 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10557kB Buffers: shared hit=145407 read=831 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=32.888..1213.443 rows=300270 loops=1) Buffers: shared hit=145407 read=831 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.045..0.109 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..0.022 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: 1kB 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 = 'ASIA'::bpchar) Rows Removed by Filter: 4 Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=905.09..6455.63 rows=60000 width=8) (actual time=31.845..221.632 rows=60054 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=145405 read=831 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=22.253..22.253 rows=60054 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=6 read=830 -> Index Scan using pk_supplier on supplier (cost=0.00..0.28 rows=1 width=8) (actual time=0.010..0.011 rows=1 loops=24633) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=74034 -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) (actual time=0.003..0.004 rows=1 loops=24633) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=49266 Total runtime: 28340.044 ms (64 rows) COMMIT; COMMIT