BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'MOROCCO' 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 = 'AFRICA' and s_nationkey = n2.n_nationkey and o_orderdate between date '1995-01-01' and date '1996-12-31' and p_type = 'ECONOMY BRUSHED STEEL' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2169596.03..2169597.86 rows=731 width=38) (actual time=32134.542..32134.542 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=723317 read=287258 dirtied=3360 written=1328 -> HashAggregate (cost=2169548.46..2169561.26 rows=731 width=38) (actual time=32134.477..32134.478 rows=2 loops=1) Buffers: shared hit=723314 read=287258 dirtied=3360 written=1328 -> Nested Loop (cost=502520.74..2169060.52 rows=24397 width=38) (actual time=23022.505..32064.832 rows=24202 loops=1) Buffers: shared hit=723314 read=287258 dirtied=3360 written=1328 -> Nested Loop (cost=502520.74..2162102.50 rows=24397 width=16) (actual time=23022.402..31872.323 rows=24202 loops=1) Buffers: shared hit=674910 read=287258 dirtied=3360 written=1328 -> Hash Join (cost=502520.74..2154998.05 rows=24397 width=16) (actual time=23022.358..31508.439 rows=24202 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=602158 read=287258 dirtied=3360 written=1328 -> Nested Loop (cost=0.00..1650223.99 rows=401870 width=16) (actual time=0.360..7163.239 rows=401573 loops=1) Buffers: shared hit=240168 read=233610 dirtied=3360 written=696 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..46064.05 rows=13240 width=4) (actual time=0.294..266.631 rows=13411 loops=1) Index Cond: (p_type = 'ECONOMY BRUSHED STEEL'::text) Heap Fetches: 13411 Buffers: shared hit=2 read=11513 written=48 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.85 rows=31 width=20) (actual time=0.047..0.498 rows=30 loops=13411) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=240166 read=222097 dirtied=3360 written=648 -> Hash (cost=491001.26..491001.26 rows=921559 width=8) (actual time=23020.678..23020.678 rows=911074 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35589kB Buffers: shared hit=361987 read=53648 written=632 -> Hash Join (cost=139082.51..491001.26 rows=921559 width=8) (actual time=5865.408..22284.151 rows=911074 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=361987 read=53648 written=632 -> Bitmap Heap Scan on orders (cost=100051.89..425475.81 rows=4607795 width=12) (actual time=3771.420..8434.678 rows=4557140 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=251939 read=17547 written=618 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..98899.94 rows=4607795 width=0) (actual time=3588.356..3588.356 rows=4612043 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared read=13179 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=2093.682..2093.682 rows=299493 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10530kB Buffers: shared hit=110048 read=36101 written=14 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=31.232..1893.172 rows=299493 loops=1) Buffers: shared hit=110048 read=36101 written=14 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.027..0.111 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=0.004..0.030 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.013..0.013 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=0.010..0.011 rows=1 loops=1) Filter: (r_name = 'AFRICA'::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=32.174..357.208 rows=59899 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=110046 read=36101 written=14 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=21.734..21.734 rows=59899 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=7 read=826 -> 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=24202) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=72752 -> 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=24202) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=48404 Total runtime: 32150.167 ms (64 rows) COMMIT; COMMIT