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 = 'PROMO PLATED STEEL' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2105180.55..2105182.37 rows=728 width=38) (actual time=35940.880..35940.880 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=768489 read=233761 dirtied=1448 written=1367 -> HashAggregate (cost=2105133.20..2105145.94 rows=728 width=38) (actual time=35940.793..35940.795 rows=2 loops=1) Buffers: shared hit=768486 read=233761 dirtied=1448 written=1367 -> Nested Loop (cost=497071.39..2104669.72 rows=23174 width=38) (actual time=26602.044..35867.920 rows=24342 loops=1) Buffers: shared hit=768486 read=233761 dirtied=1448 written=1367 -> Nested Loop (cost=497071.39..2098060.50 rows=23174 width=16) (actual time=26601.964..35649.891 rows=24342 loops=1) Buffers: shared hit=719802 read=233761 dirtied=1448 written=1367 -> Hash Join (cost=497071.39..2091309.84 rows=23182 width=16) (actual time=26601.914..35180.123 rows=24342 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=646647 read=233761 dirtied=1448 written=1367 -> Nested Loop (cost=0.00..1592088.69 rows=383586 width=16) (actual time=0.418..7520.309 rows=397675 loops=1) Buffers: shared hit=285753 read=181054 dirtied=1435 written=1037 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..44478.71 rows=12713 width=4) (actual time=0.366..271.876 rows=13251 loops=1) Index Cond: (p_type = 'PROMO PLATED STEEL'::text) Heap Fetches: 13251 Buffers: shared hit=4411 read=6971 written=55 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..121.42 rows=31 width=20) (actual time=0.059..0.531 rows=30 loops=13251) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=281342 read=174083 dirtied=1435 written=982 -> Hash (cost=485672.01..485672.01 rows=911951 width=8) (actual time=26600.106..26600.106 rows=912842 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35658kB Buffers: shared hit=360891 read=52707 dirtied=13 written=330 -> Hash Join (cost=136270.05..485672.01 rows=911951 width=8) (actual time=6697.232..25993.498 rows=912842 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=360891 read=52707 dirtied=13 written=330 -> Bitmap Heap Scan on orders (cost=97239.43..420422.79 rows=4559757 width=12) (actual time=4144.532..10565.093 rows=4557140 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=250821 read=16600 dirtied=13 written=330 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..96099.49 rows=4559757 width=0) (actual time=4009.430..4009.430 rows=4584480 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared read=12634 written=83 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=2552.422..2552.422 rows=300963 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10581kB Buffers: shared hit=110070 read=36107 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=35.554..2324.952 rows=300963 loops=1) Buffers: shared hit=110070 read=36107 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.038..0.102 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..0.021 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.020..0.020 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=0.016..0.018 rows=1 loops=1) Filter: (r_name = 'EUROPE'::bpchar) Rows Removed by Filter: 4 Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=905.09..6455.63 rows=60000 width=8) (actual time=37.079..444.283 rows=60193 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=110068 read=36107 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=27.116..27.116 rows=60193 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=6 read=833 -> Index Scan using pk_supplier on supplier (cost=0.00..0.28 rows=1 width=8) (actual time=0.017..0.017 rows=1 loops=24342) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=73155 -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) (actual time=0.005..0.006 rows=1 loops=24342) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=48684 Total runtime: 35957.067 ms (64 rows) COMMIT; COMMIT