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 = 'PROMO POLISHED COPPER' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2138972.64..2138974.47 rows=733 width=38) (actual time=32744.758..32744.758 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=747243 read=254223 dirtied=674 written=1 -> HashAggregate (cost=2138924.93..2138937.76 rows=733 width=38) (actual time=32744.672..32744.673 rows=2 loops=1) Buffers: shared hit=747240 read=254223 dirtied=674 written=1 -> Nested Loop (cost=496470.84..2138447.77 rows=23858 width=38) (actual time=24331.656..32680.892 rows=24360 loops=1) Buffers: shared hit=747240 read=254223 dirtied=674 written=1 -> Nested Loop (cost=496470.84..2131643.47 rows=23858 width=16) (actual time=24331.589..32490.751 rows=24360 loops=1) Buffers: shared hit=698520 read=254223 dirtied=674 written=1 -> Hash Join (cost=496470.84..2124695.94 rows=23858 width=16) (actual time=24331.545..32110.464 rows=24360 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=625303 read=254223 dirtied=674 written=1 -> Nested Loop (cost=0.00..1626026.17 rows=392069 width=16) (actual time=1.244..6474.710 rows=399253 loops=1) Buffers: shared hit=256710 read=210152 dirtied=422 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..45444.13 rows=13033 width=4) (actual time=1.152..234.266 rows=13296 loops=1) Index Cond: (p_type = 'PROMO POLISHED COPPER'::text) Heap Fetches: 13296 Buffers: shared hit=3327 read=8153 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.97 rows=31 width=20) (actual time=0.048..0.455 rows=30 loops=13296) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=253383 read=201999 dirtied=422 -> Hash (cost=485026.79..485026.79 rows=915524 width=8) (actual time=24328.441..24328.441 rows=913977 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35703kB Buffers: shared hit=368590 read=44071 dirtied=252 written=1 -> Hash Join (cost=136013.14..485026.79 rows=915524 width=8) (actual time=5501.596..23058.089 rows=913977 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=368590 read=44071 dirtied=252 written=1 -> Bitmap Heap Scan on orders (cost=96982.52..419674.85 rows=4577622 width=12) (actual time=3472.432..8362.708 rows=4561956 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=223242 read=43242 dirtied=252 written=1 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..95838.12 rows=4577622 width=0) (actual time=3331.740..3331.740 rows=4570988 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=2 read=12454 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=2028.871..2028.871 rows=300963 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10581kB Buffers: shared hit=145348 read=829 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=44.529..1825.608 rows=300963 loops=1) Buffers: shared hit=145348 read=829 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.052..0.120 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=0.009..0.024 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.025..0.025 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=0.022..0.023 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=40.138..343.356 rows=60193 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=145346 read=829 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=29.351..29.351 rows=60193 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=10 read=829 -> Index Scan using pk_supplier on supplier (cost=0.00..0.28 rows=1 width=8) (actual time=0.013..0.014 rows=1 loops=24360) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=73217 -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) (actual time=0.005..0.005 rows=1 loops=24360) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=48720 Total runtime: 32763.133 ms (64 rows) COMMIT; COMMIT