教义:级联=“删除"；vs orphanRemoval=true [英] Doctrine: cascade="remove" vs orphanRemoval=true

问题描述

以上两个选项有什么区别?什么时候最好选择每个选项?

What is the difference between the 2 options above? When is it preferable to choose each option?

推荐答案

它们的基本区别是:

当使用 orphanRemoval=true 选项时，Doctrine 做出假设实体是私有的，不会被其他人重用实体.如果您忽略此假设，您的实体将获得即使您将孤立实体分配给 Doctrine，也会被 Doctrine 删除另一个.

When using the orphanRemoval=true option Doctrine makes the assumption that the entities are privately owned and will NOT be reused by other entities. If you neglect this assumption your entities will get deleted by Doctrine even if you assigned the orphaned entity to another one.

假设您的 User 与 Comment 具有 一对多 关系.如果您使用 cascade="remove"，您可以从一个 UserComment 的引用>，然后将该 Comment 附加到另一个 User.当您持久保存它们时，它们将被正确保存.但是如果您使用的是 orphanRemoval=true，即使您将从一个 User 中删除给定的 Comment，然后附加到另一个用户，这个评论会在persist期间被删除，因为引用已经被删除了.

Say your User has one-to-many relation to Comment. If you are using cascade="remove", you can remove the reference for Comment from one User, and then attach that Comment to another User. When you persist them, they will be correctly saved. But if you are using orphanRemoval=true, even if you will remove given Comment from one User, and then attach to another User, this comment will be deleted during persist, because the reference has been deleted.

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