JPA嵌套选择左外部联接 [英] JPA Nested Select Left Outer Join

问题描述

是否可以在JPA QL中进行嵌套选择?

Is it possible to do a nested select in JPA QL?

如何在JPA QL中编写以下SQL语句?

How would I write the following SQL statement in JPA QL?

select * from preferences p left outer join (select * from preferencesdisplay where user_id='XXXX') display on ap.pref_id=display.pref_id;

JPA实体 PREFERENCES 与 PREFERENCESDISPLAY 具有OneToMany关系.无论是否有 PREFERENCESDISPLAY 参考，我都想获取所有的 PREFERENCES .

The JPA entity PREFERENCES has a OneToMany relationship to PREFERENCESDISPLAY. I want to get all the PREFERENCES whether or not there is a PREFERENCESDISPLAY reference.

推荐答案

在休眠状态下，您可以使用"with":

In hibernate you can use "with":

select ... from Preferences p left join p.displays d  with  d.user.id = 100

但是在JPA中，我从未见过这种可能性.

But in JPA I have never seen such possibilities.

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