nhibernate的3.3一一对多映射逐代码更新孩子而插入 [英] nhibernate 3.3 one-to-many mapping-by-code updates children instead of inserting

问题描述

我有这样一个一对多关联我'老'的NHibernate或创建流畅的时候zilions。但我上无法使其与映射按代码

I have this one-to-many association I created zilions of times with 'old' nhibernate or fluent. But I cann't make it work with mapping-by-code

以上是类

 public class Parent
 {
      public virtual IList<Child> Children { get; set; }
 }

 public class Child
 {
      public virtual Parent Parent { get; set; }
 }

没有什么奇怪的。

Nothing odd

和这些映射类

有关家长：

 Bag(x => x.Parent, m => m.Key(k => k.Column("Parent_id")));

儿童：

Child:

 ManyToOne(x => x.Children, map => { map.Column("Parent_id"); map.Cascade(Cascade.All); });

如果我做了以下

 var parent = new Parent();
 parent.Children.Add(new Child());

 session.SaveOrUpdate(parent); 

我得到了家长正确的INSERT，但它增加了对任何儿童的UPDATE

I got correct INSERT for parent, but it does an UPDATE for any child added

UPDATE TableChildren
......
WHERE Id = 0 <-????

什么是我缺少什么？我敲我的头！

What's am I missing? I'm banging my head!!

推荐答案

我看到两个问题。映射似乎反转（袋应该去孩子，多对一为父）。这里的基本设置也是逆=真。

I see two issues. The mapping seems to be inverted (Bag should go for Children, ManyToOne for a Parent). The essential setting here is also the inverse="true".

由于在这里详细记载：

• 的Mapping-by-Code - 设置和袋，我们应该补充一点：


• 映射逐码 - 多对一

• Mapping-by-Code - Set and Bag, we should add this:
• Mapping-by-Code - ManyToOne

儿童应该映射是这样的：

The Children should be mapped like this:

Bag(x => x.Children, m => 
    m.Inverse(true);
    m.Cascade(Cascade.All);
    m.Key(k => k.Column("Parent_id")));

和这样的父

ManyToOne(x => x.Parent, map => 
{ 
    map.Column("Parent_id"); 
});

的

逆=真是一个这样如何指导NHibernate的，每个孩子可以管理自己。因此，一旦孩子加入到孩子集合，我们还必须将它父！那么NHibernate的将插入孩子一步到位正确的参考。

The inverse="true" is a way how to instruct NHibernate, that each child can manage itself. So, once the child is added into the Children collection, we also have to set its Parent! NHibernate will then INSERT the child with the correct reference in one step.

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