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 ('12', '22', '32', '16', '33', '28', '29') and c_acctbal > ( select avg(c_acctbal) from customer where c_acctbal > 0.00 and substr(c_phone, 1, 2) in ('12', '22', '32', '16', '33', '28', '29') ) and not exists ( select * from orders where o_custkey = c_custkey ) ) as vip group by cntrycode order by cntrycode; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------ Sort (cost=691244.54..691244.54 rows=3 width=20) Sort Key: (substr((customer.c_phone)::text, 1, 2)) InitPlan 1 (returns $0) -> Aggregate (cost=52954.10..52954.11 rows=1 width=4) -> Bitmap Heap Scan on customer customer_1 (cost=6676.20..51997.58 rows=382605 width=4) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{12,22,32,16,33,28,29}'::text[])) AND (c_acctbal > 0::double precision)) -> Bitmap Index Scan on customer_c_phone_idx_c_acctbal (cost=0.00..6580.55 rows=382605 width=0) Index Cond: (substr((c_phone)::text, 1, 2) = ANY ('{12,22,32,16,33,28,29}'::text[])) -> HashAggregate (cost=638290.36..638290.41 rows=3 width=20) Group Key: substr((customer.c_phone)::text, 1, 2) -> Hash Anti Join (cost=594300.37..637843.41 rows=59593 width=20) Hash Cond: (customer.c_custkey = orders.o_custkey) -> Bitmap Heap Scan on customer (cost=2941.23..41902.45 rows=140313 width=24) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{12,22,32,16,33,28,29}'::text[])) AND (c_acctbal > $0)) -> Bitmap Index Scan on customer_c_phone_idx (cost=0.00..2906.15 rows=140313 width=0) Index Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{12,22,32,16,33,28,29}'::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: 1.897 ms (19 rows) COMMIT; COMMIT