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', '19', '13', '22', '10', '21', '33') and c_acctbal > ( select avg(c_acctbal) from customer where c_acctbal > 0.00 and substr(c_phone, 1, 2) in ('34', '19', '13', '22', '10', '21', '33') ) and not exists ( select * from orders where o_custkey = c_custkey ) ) as vip group by cntrycode order by cntrycode; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------ Sort (cost=691333.39..691333.40 rows=3 width=20) Sort Key: (substr((public.customer.c_phone)::text, 1, 2)) InitPlan 1 (returns $0) -> Aggregate (cost=52972.90..52972.91 rows=1 width=4) -> Bitmap Heap Scan on customer (cost=6679.34..52015.03 rows=383150 width=4) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{34,19,13,22,10,21,33}'::text[])) AND (c_acctbal > 0::double precision)) -> Bitmap Index Scan on customer_c_phone_idx_c_acctbal (cost=0.00..6583.55 rows=383150 width=0) Index Cond: (substr((c_phone)::text, 1, 2) = ANY ('{34,19,13,22,10,21,33}'::text[])) -> HashAggregate (cost=638360.41..638360.45 rows=3 width=20) -> Hash Anti Join (cost=594302.45..637914.06 rows=59513 width=20) Hash Cond: (public.customer.c_custkey = orders.o_custkey) -> Bitmap Heap Scan on customer (cost=2943.31..41912.72 rows=140625 width=24) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{34,19,13,22,10,21,33}'::text[])) AND (c_acctbal > $0)) -> Bitmap Index Scan on customer_c_phone_idx (cost=0.00..2908.16 rows=140625 width=0) Index Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{34,19,13,22,10,21,33}'::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) (17 rows) COMMIT; COMMIT