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 = 'SMALL BRUSHED NICKEL' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2161564.44..2161566.26 rows=729 width=38) (actual time=31429.205..31429.206 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=796537 read=214759 dirtied=1131 written=161 -> HashAggregate (cost=2161517.02..2161529.78 rows=729 width=38) (actual time=31429.119..31429.121 rows=2 loops=1) Buffers: shared hit=796534 read=214759 dirtied=1131 written=161 -> Nested Loop (cost=497357.84..2161034.60 rows=24121 width=38) (actual time=23577.527..31360.919 rows=24669 loops=1) Buffers: shared hit=796534 read=214759 dirtied=1131 written=161 -> Nested Loop (cost=497357.84..2154155.29 rows=24121 width=16) (actual time=23577.452..31193.856 rows=24669 loops=1) Buffers: shared hit=747196 read=214759 dirtied=1131 written=161 -> Hash Join (cost=497357.84..2147121.87 rows=24153 width=16) (actual time=23577.394..30851.193 rows=24669 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=673054 read=214759 dirtied=1131 written=161 -> Nested Loop (cost=0.00..1647527.05 rows=399090 width=16) (actual time=0.397..5910.149 rows=404514 loops=1) Buffers: shared hit=274316 read=199896 dirtied=1131 written=161 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..46027.80 rows=13227 width=4) (actual time=0.299..240.970 rows=13487 loops=1) Index Cond: (p_type = 'SMALL BRUSHED NICKEL'::text) Heap Fetches: 13487 Buffers: shared hit=3 read=11599 written=8 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.77 rows=31 width=20) (actual time=0.041..0.405 rows=30 loops=13487) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=274313 read=188297 dirtied=1131 written=153 -> Hash (cost=485942.44..485942.44 rows=913232 width=8) (actual time=23575.790..23575.790 rows=913799 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35696kB Buffers: shared hit=398735 read=14863 -> Hash Join (cost=136407.66..485942.44 rows=913232 width=8) (actual time=6820.328..22903.101 rows=913799 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=398735 read=14863 -> Bitmap Heap Scan on orders (cost=97377.04..420656.41 rows=4566158 width=12) (actual time=3887.433..8023.730 rows=4561664 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=254787 read=12634 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..96235.50 rows=4566158 width=0) (actual time=3771.797..3771.797 rows=4584480 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared read=12634 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=2932.597..2932.597 rows=300963 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10581kB Buffers: shared hit=143948 read=2229 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=37.522..1097.853 rows=300963 loops=1) Buffers: shared hit=143948 read=2229 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.041..0.115 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..0.033 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.019..0.019 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=0.017..0.017 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=33.062..201.684 rows=60193 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=143946 read=2229 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=22.437..22.437 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=0.011..0.012 rows=1 loops=24669) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=74142 -> 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=24669) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=49338 Total runtime: 31449.532 ms (64 rows) COMMIT; COMMIT