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 ('24', '32', '20', '33', '27', '29', '18') and c_acctbal > ( select avg(c_acctbal) from customer where c_acctbal > 0.00 and substr(c_phone, 1, 2) in ('24', '32', '20', '33', '27', '29', '18') ) and not exists ( select * from orders where o_custkey = c_custkey ) ) as vip group by cntrycode order by cntrycode; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------ Sort (cost=690529.00..690529.01 rows=3 width=20) Sort Key: (substr((customer.c_phone)::text, 1, 2)) InitPlan 1 (returns $0) -> Aggregate (cost=52888.82..52888.83 rows=1 width=4) -> Bitmap Heap Scan on customer customer_1 (cost=6643.41..51935.13 rows=381475 width=4) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{24,32,20,33,27,29,18}'::text[])) AND (c_acctbal > 0::double precision)) -> Bitmap Index Scan on customer_c_phone_idx_c_acctbal (cost=0.00..6548.04 rows=381475 width=0) Index Cond: (substr((c_phone)::text, 1, 2) = ANY ('{24,32,20,33,27,29,18}'::text[])) -> HashAggregate (cost=637640.10..637640.15 rows=3 width=20) Group Key: substr((customer.c_phone)::text, 1, 2) -> Hash Anti Join (cost=593677.07..637196.40 rows=59161 width=20) Hash Cond: (customer.c_custkey = orders.o_custkey) -> Bitmap Heap Scan on customer (cost=2908.07..41856.16 rows=139813 width=24) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{24,32,20,33,27,29,18}'::text[])) AND (c_acctbal > $0)) -> Bitmap Index Scan on customer_c_phone_idx (cost=0.00..2873.11 rows=139813 width=0) Index Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{24,32,20,33,27,29,18}'::text[])) AND (c_acctbal > $0)) -> Hash (cost=403269.00..403269.00 rows=15000000 width=4) -> Seq Scan on orders (cost=0.00..403269.00 rows=15000000 width=4) Planning time: 1.882 ms (19 rows) COMMIT; COMMIT