hibernate - Hibernate：是否可以通过一个连接获取两个字段？

Question

我有一个Subject有两个字段Collection<Ownership> ownershipFrom和Collection<Ownership> ownershipTo. 该类Ownership有两个字段，Subject owner并且Subject owned

要获取主题及其集合，我目前正在执行以下操作：

from Subject s left join fetch s.ownershipFrom left join fetch s.ownershipTo.

这可行，但对我来说似乎效率不高，因为我访问同一张表（所有权）两次，我相信我只能访问一次。有没有更好的方法来获取这些类？

score 0 · Accepted Answer

我将从Ownership对象而不是Subject. 例子：

select own
from Ownership own, Subject s
where own.ownershipFrom = s
or own.ownershipTo = s

类似的东西。

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