Hibernate的多对多的很多人 [英] Hibernate Many to Many on many to

问题描述

我正尝试映射现有的数据库使用注释休眠。
问题是如下

I´m trying to map an existing database to Hibernate using annotations. The problem is as follows.

组织和organization_roles'有一个多对多的关系是在解决
表'organization_has_roles使用两个主键作为联结表中的复合主键。

'organization' and 'organization_roles' has a many to many relationship which is resolved in a table 'organization_has_roles' using the two primary keys as a composite primary key in the join table.

接下来是一个用户表。用户可以在多个组织的单一角色。这又是解决了一个名为users_has_organizations_and_role里面有USER_ID，organization_id'和'organization_role_id'和对'USER_ID和organization_id一unique_index的复合主键连接表。

Next there is a 'users' table. Users can have a single role in multiple organizations. This is again resolved in a join table named 'users_has_organizations_and_role' which has a composite primary key of the 'user_id', 'organization_id' and 'organization_role_id' and a unique_index on the 'user_id' and 'organization_id'.

在'users_has_organizations_and_role'引用'organization_has_roles复合主键（organization_id，organization_role_id）和用户表（USER_ID）

The 'users_has_organizations_and_role' references the 'organization_has_roles' composite primary key(organization_id, organization_role_id) and the users table (user_id)

我一直没能找到关于这一问题的工作的例子。

I have not been able to find examples on this matter that worked.

是否有可能映射这一点。这批注我应该用怎么样？

Is it possible to map this. Which Annotations should I use and how?

I'm使用Hibernate 4，尽管它可能并不重要。

I´m using Hibernate 4, although it might not matter..

推荐答案

这种方法的主要问题是，你有一个不可映射ORM不匹配：​​您在数据库中有一个实体（ organization_has_roles ），它被翻译为于二OO的关系。因为这种关系不是一个实体，并且没有 @Id ，它不能被引用到另一个实体。

The main problem with this approach is that you have an unmappable ORM mismatch: you have an entity in your database (organization_has_roles) which is translated as a relationship in OO. As this relationship is not an entity, and has no @Id, it cannot be referenced into yet another entity.

一个解决方案是将数据库实体 organization_has_roles 映射到JPA / Hibernate的实体，无论是复合键，或用合成关键（不管你preFER ）。然后，您可以参考这个实体在用户模式。

A solution is to map the database entity organization_has_roles into a JPA/Hibernate entity, with either a composite key, or with a synthetic key (whatever you prefer). You can then refer to this entity in your User model.

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