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 ('32', '11', '33', '26', '23', '34', '17') and c_acctbal > ( select avg(c_acctbal) from customer where c_acctbal > 0.00 and substr(c_phone, 1, 2) in ('32', '11', '33', '26', '23', '34', '17') ) and not exists ( select * from orders where o_custkey = c_custkey ) ) as vip group by cntrycode order by cntrycode; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------ Sort (cost=691171.02..691171.03 rows=3 width=20) Sort Key: (substr((public.customer.c_phone)::text, 1, 2)) InitPlan 1 (returns $0) -> Aggregate (cost=52886.71..52886.72 rows=1 width=4) -> Bitmap Heap Scan on customer (cost=6642.10..51933.09 rows=381447 width=4) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{32,11,33,26,23,34,17}'::text[])) AND (c_acctbal > 0::double precision)) -> Bitmap Index Scan on customer_c_phone_idx_c_acctbal (cost=0.00..6546.74 rows=381447 width=0) Index Cond: (substr((c_phone)::text, 1, 2) = ANY ('{32,11,33,26,23,34,17}'::text[])) -> HashAggregate (cost=638284.24..638284.28 rows=3 width=20) -> Hash Anti Join (cost=594267.35..637841.13 rows=59081 width=20) Hash Cond: (public.customer.c_custkey = orders.o_custkey) -> Bitmap Heap Scan on customer (cost=2908.21..41859.32 rows=139928 width=24) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{32,11,33,26,23,34,17}'::text[])) AND (c_acctbal > $0)) -> Bitmap Index Scan on customer_c_phone_idx (cost=0.00..2873.23 rows=139928 width=0) Index Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{32,11,33,26,23,34,17}'::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