NHibernate读取单个字段值，错误修改方法

原语句：

IQuery query = DbHelper.Session.CreateQuery("select Id from Member where UserName=:username");
query.SetString("username", username);
object reslut = query.UniqueResult();



读取单个字段值，报如下错误：

undefined alias or unknown mapping: Id



修正语句

IQuery query = DbHelper.Session.CreateQuery("select member.Id from Member as member where UserName=:username");
query.SetString("username", username);
object reslut = query.UniqueResult();



读取单个字段时，要注意加上别名，程序正常通过。