select sum(p.point) as sum_balan,p.customer
from point_transaction p ,customer c
where p.customer=c.id
group by p.customer
聚合函数 使用group by时候,前面出现的字段,group by 时一定要出现
select sum(p.point) as sum_balan,p.customer
from point_transaction p ,customer c
where p.customer=c.id
group by p.customer
聚合函数 使用group by时候,前面出现的字段,group by 时一定要出现