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', '32', '30', '13', '22', '12', '20') and c_acctbal > ( select avg(c_acctbal) from customer where c_acctbal > 0.00 and substr(c_phone, 1, 2) in ('24', '32', '30', '13', '22', '12', '20') ) and not exists ( select * from orders where o_custkey = c_custkey ) ) as vip group by cntrycode order by cntrycode; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------ Sort (cost=691255.66..691255.67 rows=3 width=20) Sort Key: (substr((customer.c_phone)::text, 1, 2)) InitPlan 1 (returns $0) -> Aggregate (cost=52960.54..52960.55 rows=1 width=4) -> Bitmap Heap Scan on customer customer_1 (cost=6677.56..52003.58 rows=382782 width=4) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{24,32,30,13,22,12,20}'::text[])) AND (c_acctbal > 0::double precision)) -> Bitmap Index Scan on customer_c_phone_idx_c_acctbal (cost=0.00..6581.86 rows=382782 width=0) Index Cond: (substr((c_phone)::text, 1, 2) = ANY ('{24,32,30,13,22,12,20}'::text[])) -> HashAggregate (cost=638295.04..638295.08 rows=3 width=20) Group Key: substr((customer.c_phone)::text, 1, 2) -> Hash Anti Join (cost=594301.02..637847.88 rows=59621 width=20) Hash Cond: (customer.c_custkey = orders.o_custkey) -> Bitmap Heap Scan on customer (cost=2941.88..41904.80 rows=140378 width=24) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{24,32,30,13,22,12,20}'::text[])) AND (c_acctbal > $0)) -> Bitmap Index Scan on customer_c_phone_idx (cost=0.00..2906.78 rows=140378 width=0) Index Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{24,32,30,13,22,12,20}'::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: 1.647 ms (19 rows) COMMIT; COMMIT