NHibernate 到现有对象的多对多映射
我尝试创建的多对多关系遇到一些问题。目标是保存客户以及允许他们购买哪些产品。这些产品并不是客户独有的，在我们尝试将客户与它们关联之前，它们始终存在于数据库中。
我的关联映射当前看起来像...
<set name="AllowedProducts" table="Customer_AllowedProducts">
<key column="CustomerId"></key>
<many-to-many class="Product" column="ProductId"/>
</set>
如果我尝试保存客户，我会收到引用该产品的 NHibernate.TransientObjectException 。我知道我可以向集合中添加级联，但我从不想在保存客户时更新或保存产品，我们只想将客户映射到现有产品。
我应该注意到，我尝试保存的客户来自 Web 服务调用，因此不会引用先前已加载到会话中的产品。我想避免必须加载将映射到会话中的每个产品。
谢谢
I'm having some issues with a many-to-many relationship I am trying to create. The goal is to save a customer and which products they are allowed to purchase. The products are not unique to a customer and will ALWAYS exist in the database before we try to associate a customer to them.
My mapping for the association currently looks like...
<set name="AllowedProducts" table="Customer_AllowedProducts">
<key column="CustomerId"></key>
<many-to-many class="Product" column="ProductId"/>
</set>
If I try to save a Customer I get a NHibernate.TransientObjectException referencing the product. I understand that I could add cascade to the set, but I NEVER want to update or save a product when saving a customer, we only want to map a customer to existing products.
I should note that the customer I'm trying to save is coming in from a webservice call and therefore does not reference products that have been previously loaded into the session. I would like to avoid have to load every product that will be mapped into the session.
Thanks
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您的代码应该如下所示：
而不是您可能正在做的事情：
值得注意的是
Loadnever 进入数据库；它只返回一个代理（或检索到的实例，如果当前会话中存在）Your code should look like this:
Instead of what you are probably doing:
It's worth noting that
Loadnever goes to the DB; it just returns a proxy (or a retrieved instance, if one is present in the current session)您必须将产品附加到休眠会话，以便它们成为托管实体。据我所知，没有其他出路。
You will have to attach the product to hibernate session so that they become managed entity. As far as I know, there is no other way out.