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 ('14', '28', '23', '12', '15', '32', '24') and c_acctbal > ( select avg(c_acctbal) from customer where c_acctbal > 0.00 and substr(c_phone, 1, 2) in ('14', '28', '23', '12', '15', '32', '24') ) and not exists ( select * from orders where o_custkey = c_custkey ) ) as vip group by cntrycode order by cntrycode; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------ Sort (cost=691297.26..691297.27 rows=3 width=20) Sort Key: (substr((public.customer.c_phone)::text, 1, 2)) InitPlan 1 (returns $0) -> Aggregate (cost=52961.89..52961.90 rows=1 width=4) -> Bitmap Heap Scan on customer (cost=6677.01..52004.77 rows=382848 width=4) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{14,28,23,12,15,32,24}'::text[])) AND (c_acctbal > 0::double precision)) -> Bitmap Index Scan on customer_c_phone_idx_c_acctbal (cost=0.00..6581.29 rows=382848 width=0) Index Cond: (substr((c_phone)::text, 1, 2) = ANY ('{14,28,23,12,15,32,24}'::text[])) -> HashAggregate (cost=638335.30..638335.34 rows=3 width=20) -> Hash Anti Join (cost=594299.65..637887.58 rows=59696 width=20) Hash Cond: (public.customer.c_custkey = orders.o_custkey) -> Bitmap Heap Scan on customer (cost=2940.51..41902.78 rows=140353 width=24) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{14,28,23,12,15,32,24}'::text[])) AND (c_acctbal > $0)) -> Bitmap Index Scan on customer_c_phone_idx (cost=0.00..2905.43 rows=140353 width=0) Index Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{14,28,23,12,15,32,24}'::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