HQL with Null检查一对一关系 [英] HQL with Null check for one-to-one relation

问题描述

在Hibernate中我有以下一对一关系（可能为null）：

 < one- to-one name =detailsclass =com.example.Detailslazy =falsecascade =all/> 
  

我试图选择所有具有HQL的非空细节的实体：

$来自实体e的b
$ b

 ，其中e.details不为空
  

，但是这会返回所有实体，无论细节是否为null。

那么正确的HQL会是什么？

好的我找到解决方案：

 从实体中选择e加入e.details d其中d不为空
  

I have the following one-to-one relation in Hibernate (that could be null):

<one-to-one name="details" class="com.example.Details" lazy="false" cascade="all"/>

I am trying to select all entities that have non-null details with HQL:

from Entity e where e.details is not null

but this returns all entities, no matter whether details are null or not.

What would be a correct HQL then?

解决方案

Ok I found the solution:

select e from Entity e join e.details d where d is not null

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