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 ('29', '24', '13', '20', '10', '27', '14') and c_acctbal > ( select avg(c_acctbal) from customer where c_acctbal > 0.00 and substr(c_phone, 1, 2) in ('29', '24', '13', '20', '10', '27', '14') ) and not exists ( select * from orders where o_custkey = c_custkey ) ) as vip group by cntrycode order by cntrycode; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------ Sort (cost=691064.91..691064.92 rows=3 width=20) Sort Key: (substr((customer.c_phone)::text, 1, 2)) InitPlan 1 (returns $0) -> Aggregate (cost=52844.85..52844.86 rows=1 width=4) -> Bitmap Heap Scan on customer customer_1 (cost=6634.08..51894.17 rows=380270 width=4) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{29,24,13,20,10,27,14}'::text[])) AND (c_acctbal > 0::double precision)) -> Bitmap Index Scan on customer_c_phone_idx_c_acctbal (cost=0.00..6539.01 rows=380270 width=0) Index Cond: (substr((c_phone)::text, 1, 2) = ANY ('{29,24,13,20,10,27,14}'::text[])) -> HashAggregate (cost=638219.99..638220.03 rows=3 width=20) Group Key: substr((customer.c_phone)::text, 1, 2) -> Hash Anti Join (cost=594264.48..637780.80 rows=58558 width=20) Hash Cond: (customer.c_custkey = orders.o_custkey) -> Bitmap Heap Scan on customer (cost=2905.34..41846.40 rows=139545 width=24) Recheck Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{29,24,13,20,10,27,14}'::text[])) AND (c_acctbal > $0)) -> Bitmap Index Scan on customer_c_phone_idx (cost=0.00..2870.45 rows=139545 width=0) Index Cond: ((substr((c_phone)::text, 1, 2) = ANY ('{29,24,13,20,10,27,14}'::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: 2.046 ms (19 rows) COMMIT; COMMIT