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 ('26', '11', '28', '33', '34', '31', '25') and c_acctbal > ( select avg(c_acctbal) from customer where c_acctbal > 0.00 and substr(c_phone, 1, 2) in ('26', '11', '28', '33', '34', '31', '25') ) and not exists ( select * from orders where o_custkey = c_custkey ) ) as vip group by cntrycode order by cntrycode; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------ Sort (cost=691711.90..691711.91 rows=3 width=20) Sort Key: (substr((public.customer.c_phone)::text, 1, 2)) InitPlan 1 (returns $0) -> Aggregate (cost=52912.65..52912.66 rows=1 width=4) -> Bitmap Heap Scan on customer (cost=6647.64..51957.26 rows=382157 width=4) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{26,11,28,33,34,31,25}'::text[])) AND (c_acctbal > 0::double precision)) -> Bitmap Index Scan on customer_c_phone_idx_c_acctbal (cost=0.00..6552.10 rows=382157 width=0) Index Cond: (substr((c_phone)::text, 1, 2) = ANY ('{26,11,28,33,34,31,25}'::text[])) -> HashAggregate (cost=638799.17..638799.22 rows=3 width=20) -> Hash Anti Join (cost=594269.00..638354.66 rows=59268 width=20) Hash Cond: (public.customer.c_custkey = orders.o_custkey) -> Bitmap Heap Scan on customer (cost=2909.86..41865.27 rows=140092 width=24) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{26,11,28,33,34,31,25}'::text[])) AND (c_acctbal > $0)) -> Bitmap Index Scan on customer_c_phone_idx (cost=0.00..2874.84 rows=140092 width=0) Index Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{26,11,28,33,34,31,25}'::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