HQL在一个集合中排序 [英] HQL order by within a collection

问题描述

我有两个实体：汽车和车轮（oneToMany），我想要检索我的车，所有的车轮和（这是棘手的部分）wheel.location。下面的代码抛出一个异常，并显示非法尝试解除引用集合的消息。

 从Car $中选择c 
 b $ b LEFT JOIN FETCH c.wheels 
 order by c.wheels.location 
  

任何想法如何做到这一点，如果这可能在HQL？

解决方案

  SELECT DISTINCT c 
 FROM car 
 LEFT JOIN FETCH c.wheels AS wheel 
 ORDER BY wheels.location 
  

I have 2 entities: car and wheels (oneToMany) and I want to retrieve my car, with all the wheels and (this is the tricky part) ordered by wheels.location. The below code throws an exception with the message "illegal attempt to dereference collection."

Select c
  from Car
       LEFT JOIN FETCH c.wheels
order by c.wheels.location

Any idea how to do this and if this is possible in HQL?

解决方案

SELECT DISTINCT c
  FROM Car
       LEFT JOIN FETCH c.wheels AS wheels
ORDER BY wheels.location

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