BEGIN; BEGIN EXPLAIN select cntrycode, count(*) as numcust, sum(c_acctbal) as totacctbal from ( select substr(c_phone, 1, 2) as cntrycode, c_acctbal from customer where substr(c_phone, 1, 2) in ('34', '28', '33', '17', '23', '22', '13') and c_acctbal > ( select avg(c_acctbal) from customer where c_acctbal > 0.00 and substr(c_phone, 1, 2) in ('34', '28', '33', '17', '23', '22', '13') ) and not exists ( select * from orders where o_custkey = c_custkey ) ) as vip group by cntrycode order by cntrycode; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------ Sort (cost=691149.77..691149.78 rows=3 width=20) Sort Key: (substr((customer.c_phone)::text, 1, 2)) InitPlan 1 (returns $0) -> Aggregate (cost=52895.69..52895.70 rows=1 width=4) -> Bitmap Heap Scan on customer customer_1 (cost=6644.88..51941.53 rows=381663 width=4) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{34,28,33,17,23,22,13}'::text[])) AND (c_acctbal > 0::double precision)) -> Bitmap Index Scan on customer_c_phone_idx_c_acctbal (cost=0.00..6549.46 rows=381663 width=0) Index Cond: (substr((c_phone)::text, 1, 2) = ANY ('{34,28,33,17,23,22,13}'::text[])) -> HashAggregate (cost=638254.00..638254.04 rows=3 width=20) Group Key: substr((customer.c_phone)::text, 1, 2) -> Hash Anti Join (cost=594269.29..637813.27 rows=58764 width=20) Hash Cond: (customer.c_custkey = orders.o_custkey) -> Bitmap Heap Scan on customer (cost=2910.15..41863.59 rows=140017 width=24) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{34,28,33,17,23,22,13}'::text[])) AND (c_acctbal > $0)) -> Bitmap Index Scan on customer_c_phone_idx (cost=0.00..2875.14 rows=140017 width=0) Index Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{34,28,33,17,23,22,13}'::text[])) AND (c_acctbal > $0)) -> Hash (cost=403671.84..403671.84 rows=15014984 width=4) -> Seq Scan on orders (cost=0.00..403671.84 rows=15014984 width=4) Planning time: 7.995 ms (19 rows) COMMIT; COMMIT