BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'GERMANY' 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 = 'ECONOMY PLATED STEEL' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2188425.17..2188427.00 rows=731 width=38) (actual time=29822.633..29822.633 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=736854 read=289846 dirtied=3137 written=5445 -> HashAggregate (cost=2188377.60..2188390.40 rows=731 width=38) (actual time=29822.580..29822.583 rows=2 loops=1) Buffers: shared hit=736851 read=289846 dirtied=3137 written=5445 -> Nested Loop (cost=502986.14..2187883.00 rows=24730 width=38) (actual time=20578.267..29750.993 rows=25374 loops=1) Buffers: shared hit=736851 read=289846 dirtied=3137 written=5445 -> Nested Loop (cost=502986.14..2180830.01 rows=24730 width=16) (actual time=20578.195..29556.008 rows=25374 loops=1) Buffers: shared hit=686103 read=289846 dirtied=3137 written=5445 -> Hash Join (cost=502986.14..2173628.59 rows=24730 width=16) (actual time=20578.145..29176.399 rows=25374 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=609866 read=289846 dirtied=3137 written=5445 -> Nested Loop (cost=0.00..1668358.43 rows=407345 width=16) (actual time=0.325..7453.097 rows=410490 loops=1) Buffers: shared hit=207959 read=275822 dirtied=3137 written=5445 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..46562.97 rows=13407 width=4) (actual time=0.265..246.016 rows=13689 loops=1) Index Cond: (p_type = 'ECONOMY PLATED STEEL'::text) Heap Fetches: 13689 Buffers: shared hit=3039 read=8724 written=234 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.66 rows=31 width=20) (actual time=0.045..0.510 rows=30 loops=13689) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=204920 read=267098 dirtied=3137 written=5211 -> Hash (cost=491455.28..491455.28 rows=922469 width=8) (actual time=20576.747..20576.747 rows=913872 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35699kB Buffers: shared hit=401904 read=14024 -> Hash Join (cost=139189.14..491455.28 rows=922469 width=8) (actual time=3979.930..20116.760 rows=913872 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=401904 read=14024 -> Bitmap Heap Scan on orders (cost=100158.52..425903.68 rows=4612344 width=12) (actual time=3129.708..6939.315 rows=4561702 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=256560 read=13191 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..99005.43 rows=4612344 width=0) (actual time=2980.086..2980.086 rows=4616605 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared read=13191 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=849.831..849.831 rows=300963 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10581kB Buffers: shared hit=145344 read=833 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=28.173..754.392 rows=300963 loops=1) Buffers: shared hit=145344 read=833 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.026..0.049 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=0.003..0.009 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.012..0.012 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=0.009..0.009 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=21.820..139.043 rows=60193 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=145342 read=833 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=14.701..14.701 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=0.012..0.013 rows=1 loops=25374) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=76237 -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) (actual time=0.004..0.005 rows=1 loops=25374) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=50748 Total runtime: 29832.657 ms (64 rows) COMMIT; COMMIT