关于实体框架：NHibernate FetchMany是否超过两个表？

Is NHibernate FetchMany on more than two tables broken?

鉴于此：

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namespace TheEntities
{
[DataContract(IsReference=true)]
public class Question
{
[DataMember] public virtual int QuestionId { get; set; }
[DataMember] public virtual string Text { get; set; }
[DataMember] public virtual string Poster { get; set; }

[DataMember] public virtual IList<QuestionComment> Comments { get; set; }
[DataMember] public virtual IList<Answer> Answers{ get; set; }

[DataMember] public virtual byte[] RowVersion { get; set; }
}

[DataContract]
public class QuestionComment
{
[DataMember] public virtual Question Question { get; set; }

[DataMember] public virtual int QuestionCommentId { get; set; }
[DataMember] public virtual string Text { get; set; }
[DataMember] public virtual string Poster { get; set; }
}

[DataContract(IsReference = true)]
public class Answer
{
[DataMember] public virtual Question Question { get; set; }

[DataMember] public virtual int AnswerId { get; set; }
[DataMember] public virtual string Text { get; set; }
[DataMember] public virtual string Poster { get; set; }

[DataMember] public virtual IList<AnswerComment> Comments { get; set; }

}

[DataContract]
public class AnswerComment
{
[DataMember] public virtual Answer Answer { get; set; }

[DataMember] public virtual int AnswerCommentId { get; set; }
[DataMember] public virtual string Text { get; set; }
[DataMember] public virtual string Poster { get; set; }
}

}

实体框架没有为answer、questioncomment和answercomment生成重复的对象，而nhibernate没有。

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public Question OpenQuestion(int id)
{
var repo = QuestionRepository;

var query = repo.All.Where(y => y.QuestionId == id);

if (QuestionRepository.GetType() == typeof(EfRepository<Question>))
{
query = query
.Include("Answers")
.Include("Answers.Comments")
.Include("Comments");

return query.Single();
}
else if (QuestionRepository.GetType() == typeof(NhRepository<Question>))
{
// kinda sad, produces duplicate objects
query = query
.FetchMany(x => x.Answers)
.ThenFetchMany(x => x.Comments)
.FetchMany(x => x.Comments);
}
else
throw new Exception("Something unsupported");

return query.Single();
}

这也会生成重复的对象(三层深度，使用三个关系)：

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query = query
.FetchMany(x => x.Answers)
.ThenFetchMany(x => x.Comments)

这也会生成重复的对象(仅两层深度，但使用三个关系)：

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query = query
.FetchMany(x => x.Answers)
.FetchMany(x => x.Comments);

这不会产生重复的对象，但是热切的加载只针对两个层次的深度和两个关系，即从问题到答案。对于要提问的注释和要回答的注释，它们是在单独的查询上执行的。

1 2	query = query .FetchMany(x => x.Answers);

如果nHibernate只能在只有两个关系的情况下为两个级别的fetchmany做好它的工作，为什么还要创建fetchmany(用于三个级别，但有错误，有重复的对象)？事实上，即使fetchmany也没用，如果你想在三个关系上使用它，它也会产生重复的对象。

NHibernate团队是否会因为不能正常工作而费心移除fetchmany？

在我的映射中没有错误，当我删除提取策略时，事情正常工作(即不产生重复的对象)。