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', '17', '27', '10', '26', '19', '18') and c_acctbal > ( select avg(c_acctbal) from customer where c_acctbal > 0.00 and substr(c_phone, 1, 2) in ('32', '17', '27', '10', '26', '19', '18') ) and not exists ( select * from orders where o_custkey = c_custkey ) ) as vip group by cntrycode order by cntrycode; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------ Sort (cost=691080.38..691080.39 rows=3 width=20) Sort Key: (substr((customer.c_phone)::text, 1, 2)) InitPlan 1 (returns $0) -> Aggregate (cost=52862.08..52862.09 rows=1 width=4) -> Bitmap Heap Scan on customer customer_1 (cost=6637.77..51910.22 rows=380741 width=4) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{32,17,27,10,26,19,18}'::text[])) AND (c_acctbal > 0::double precision)) -> Bitmap Index Scan on customer_c_phone_idx_c_acctbal (cost=0.00..6542.58 rows=380741 width=0) Index Cond: (substr((c_phone)::text, 1, 2) = ANY ('{32,17,27,10,26,19,18}'::text[])) -> HashAggregate (cost=638218.23..638218.27 rows=3 width=20) Group Key: substr((customer.c_phone)::text, 1, 2) -> Hash Anti Join (cost=594264.77..637777.43 rows=58773 width=20) Hash Cond: (customer.c_custkey = orders.o_custkey) -> Bitmap Heap Scan on customer (cost=2905.63..41847.42 rows=139573 width=24) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{32,17,27,10,26,19,18}'::text[])) AND (c_acctbal > $0)) -> Bitmap Index Scan on customer_c_phone_idx (cost=0.00..2870.73 rows=139573 width=0) Index Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{32,17,27,10,26,19,18}'::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) Planning time: 1.902 ms (19 rows) COMMIT; COMMIT