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 ('24', '34', '15', '23', '12', '28', '13') and c_acctbal > ( select avg(c_acctbal) from customer where c_acctbal > 0.00 and substr(c_phone, 1, 2) in ('24', '34', '15', '23', '12', '28', '13') ) and not exists ( select * from orders where o_custkey = c_custkey ) ) as vip group by cntrycode order by cntrycode; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------ Sort (cost=691132.20..691132.21 rows=3 width=20) Sort Key: (substr((customer.c_phone)::text, 1, 2)) InitPlan 1 (returns $0) -> Aggregate (cost=52885.47..52885.48 rows=1 width=4) -> Bitmap Heap Scan on customer customer_1 (cost=6642.71..51932.01 rows=381383 width=4) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{24,34,15,23,12,28,13}'::text[])) AND (c_acctbal > 0::double precision)) -> Bitmap Index Scan on customer_c_phone_idx_c_acctbal (cost=0.00..6547.36 rows=381383 width=0) Index Cond: (substr((c_phone)::text, 1, 2) = ANY ('{24,34,15,23,12,28,13}'::text[])) -> HashAggregate (cost=638246.65..638246.69 rows=3 width=20) Group Key: substr((customer.c_phone)::text, 1, 2) -> Hash Anti Join (cost=594268.71..637804.85 rows=58906 width=20) Hash Cond: (customer.c_custkey = orders.o_custkey) -> Bitmap Heap Scan on customer (cost=2909.57..41861.47 rows=139958 width=24) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{24,34,15,23,12,28,13}'::text[])) AND (c_acctbal > $0)) -> Bitmap Index Scan on customer_c_phone_idx (cost=0.00..2874.58 rows=139958 width=0) Index Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{24,34,15,23,12,28,13}'::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: 1.791 ms (19 rows) COMMIT; COMMIT