休眠标准：没有映射关联的连接表 [英] Hibernate criteria: Joining table without a mapped association

问题描述

我想用Hibernate的标准api来制定一个连接两个实体的特定查询。比方说，我有两个实体，一个拥有宠物的拥有者的宠物和所有者，但最关键的是该关联未映射到Java注释或xml中。

使用hql，I可以通过在查询中指定连接来选择拥有名为'fido'的宠物的所有者（而不是将一组宠物添加到所有者类）。

可以相同使用休眠标准来完成？如果是这样的话，怎么样？

感谢，
J

解决方案

我的理解是，如果你使用HQL来做到这一点，那么你使用过滤器创建笛卡尔联接，而不是使用内部联接。标准查询不支持这样做。

I'd like to use Hibernate's criteria api to formulate a particular query that joins two entities. Let's say I have two entities, Pet and Owner with a owner having many pets, but crucially that association is not mapped in the Java annotations or xml.

With hql, I could select owners that have a pet called 'fido' by specifying the join in the query (rather than adding a set of pets to the owner class).

Can the same be done using hibernate criteria? If so how?

Thanks, J

解决方案

My understanding is that if you do this using HQL, you are creating a Cartesian join with a filter, rather than an inner join. Criteria queries do not support doing this.

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