同样的sql语句为什么在mysql下可以运行 在php里去不行

语句为 select a.charge_person,a.charge_money,a.time_insert,b.time_insert,sum(b.moneys),(a.charge_money-sum(b.moneys))balance from (advcharge a) left join (basic b) on (a.charge_person=b.contact) where (b.time_insert>a.time_insert) group by chagre_person;  语句为 select a.charge_person,a.charge_money,a.tim