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', '10', '33', '22', '12', '30', '27') and c_acctbal > ( select avg(c_acctbal) from customer where c_acctbal > 0.00 and substr(c_phone, 1, 2) in ('26', '10', '33', '22', '12', '30', '27') ) and not exists ( select * from orders where o_custkey = c_custkey ) ) as vip group by cntrycode order by cntrycode; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------ Sort (cost=691167.16..691167.17 rows=3 width=20) Sort Key: (substr((public.customer.c_phone)::text, 1, 2)) InitPlan 1 (returns $0) -> Aggregate (cost=52888.18..52888.19 rows=1 width=4) -> Bitmap Heap Scan on customer (cost=6642.43..51934.46 rows=381487 width=4) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{26,10,33,22,12,30,27}'::text[])) AND (c_acctbal > 0::double precision)) -> Bitmap Index Scan on customer_c_phone_idx_c_acctbal (cost=0.00..6547.06 rows=381487 width=0) Index Cond: (substr((c_phone)::text, 1, 2) = ANY ('{26,10,33,22,12,30,27}'::text[])) -> HashAggregate (cost=638278.90..638278.95 rows=3 width=20) -> Hash Anti Join (cost=594267.35..637833.41 rows=59399 width=20) Hash Cond: (public.customer.c_custkey = orders.o_custkey) -> Bitmap Heap Scan on customer (cost=2908.21..41859.45 rows=139933 width=24) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{26,10,33,22,12,30,27}'::text[])) AND (c_acctbal > $0)) -> Bitmap Index Scan on customer_c_phone_idx (cost=0.00..2873.23 rows=139933 width=0) Index Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{26,10,33,22,12,30,27}'::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