BEGIN; BEGIN EXPLAIN select o_year, sum(case when nation = 'UNITED STATES' 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 = 'AMERICA' and s_nationkey = n2.n_nationkey and o_orderdate between date '1995-01-01' and date '1996-12-31' and p_type = 'SMALL BURNISHED COPPER' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2173104.18..2173106.00 rows=730 width=38) Sort Key: (date_part('year'::text, (orders.o_orderdate)::timestamp without time zone)) -> HashAggregate (cost=2173056.69..2173069.46 rows=730 width=38) -> Nested Loop (cost=494909.45..2172570.61 rows=24304 width=38) -> Nested Loop (cost=494909.45..2165639.10 rows=24304 width=16) -> Hash Join (cost=494909.45..2158553.83 rows=24331 width=16) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) -> Nested Loop (cost=0.00..1661394.51 rows=401312 width=16) -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..46442.41 rows=13367 width=4) Index Cond: (p_type = 'SMALL BURNISHED COPPER'::text) -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.51 rows=31 width=20) Index Cond: (l_partkey = part.p_partkey) -> Hash (cost=483530.43..483530.43 rows=910322 width=8) -> Hash Join (cost=135562.52..483530.43 rows=910322 width=8) Hash Cond: (orders.o_custkey = customer.c_custkey) -> Bitmap Heap Scan on orders (cost=96531.90..418328.05 rows=4551610 width=12) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..95394.00 rows=4551610 width=0) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) -> Hash (cost=35280.62..35280.62 rows=300000 width=4) -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) -> Hash Join (cost=1.07..2.47 rows=5 width=4) Hash Cond: (n1.n_regionkey = region.r_regionkey) -> Seq Scan on nation n1 (cost=0.00..1.25 rows=25 width=8) -> Hash (cost=1.06..1.06 rows=1 width=4) -> Seq Scan on region (cost=0.00..1.06 rows=1 width=4) Filter: (r_name = 'AMERICA'::bpchar) -> Bitmap Heap Scan on customer (cost=905.09..6455.63 rows=60000 width=8) Recheck Cond: (c_nationkey = n1.n_nationkey) -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) Index Cond: (c_nationkey = n1.n_nationkey) -> Index Scan using pk_supplier on supplier (cost=0.00..0.28 rows=1 width=8) Index Cond: (s_suppkey = lineitem.l_suppkey) -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) Index Cond: (n_nationkey = supplier.s_nationkey) (35 rows) COMMIT; COMMIT