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 ('11', '16', '32', '15', '20', '30', '19') and c_acctbal > ( select avg(c_acctbal) from customer where c_acctbal > 0.00 and substr(c_phone, 1, 2) in ('11', '16', '32', '15', '20', '30', '19') ) and not exists ( select * from orders where o_custkey = c_custkey ) ) as vip group by cntrycode order by cntrycode; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------ Sort (cost=691154.70..691154.71 rows=3 width=20) Sort Key: (substr((public.customer.c_phone)::text, 1, 2)) InitPlan 1 (returns $0) -> Aggregate (cost=52882.36..52882.37 rows=1 width=4) -> Bitmap Heap Scan on customer (cost=6641.18..51929.04 rows=381328 width=4) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{11,16,32,15,20,30,19}'::text[])) AND (c_acctbal > 0::double precision)) -> Bitmap Index Scan on customer_c_phone_idx_c_acctbal (cost=0.00..6545.85 rows=381328 width=0) Index Cond: (substr((c_phone)::text, 1, 2) = ANY ('{11,16,32,15,20,30,19}'::text[])) -> HashAggregate (cost=638272.26..638272.30 rows=3 width=20) -> Hash Anti Join (cost=594265.48..637830.28 rows=58930 width=20) Hash Cond: (public.customer.c_custkey = orders.o_custkey) -> Bitmap Heap Scan on customer (cost=2906.34..41852.65 rows=139745 width=24) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{11,16,32,15,20,30,19}'::text[])) AND (c_acctbal > $0)) -> Bitmap Index Scan on customer_c_phone_idx (cost=0.00..2871.41 rows=139745 width=0) Index Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{11,16,32,15,20,30,19}'::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