注意group by 和having子句的使用
select a.clmno,sum(a.realpay) from llclaimdetail a where 1=1 group by a.clmno having sum(a.realpay)=0
SQL语句-查询费用总和为0的案件号
原文：https://www.cnblogs.com/dongyaotou/p/12173484.html
