删除不会nulled直到保存：是真的吗？ [英] Deleting won't nullify until save : is it true?

问题描述

我的情况：我在核心数据中有复杂的（24个实体，许多关系和许多有序到多个关系）模型。

现在让我们说，我有一个实体 PlayList 和实体 Song ，在 PlayList 与 Song 的有序对多关系。这个关系有一个逆，并且都有一个 nullify 删除规则。

我注意到，当我删除属于 PlayList的 Song （让我们称为 gangnam c>，这首歌不会从关系中删除！我尝试用以下方法解决这个问题：

• 我修复了与多对有序关系相关的Apple的错误， a href =https://github.com/CFKevinRef/KCOrderedAccessorFix =nofollow> KCOrderedAccessorFix 。顺便说一下，如果你使用其他解决方案，要小心，因为错误不仅是对于 addAnObject 部分，而且对于 removeAnObject 部分。 结果：好多了，但仍然无法工作：我的关系还指 gangnam ：（


• ： processPendingChanges ：无效。

，

• 如果我保存我的上下文，


因此，我的问题是：

如果我想要 save > nullify 关系？
或者我缺少某些东西？

我试图重现bug一个较小的模型，但在这种情况下，调用 processPendingChanges 就足以 nullify 同样的问题/情况，我很高兴地知道，我不是唯一一个与核心数据;）

战斗 =h2_lin>解决方案

由于一个原因，实体的图形是不一致的（ CoreData 的一个错误）它们的逆不被适当地保持）。所以，它拒绝删除对象。如果我保存，它首先使图形一致，然后可以删除该对象。

My situation : I have complex (24 entities, many relationships and many ordered to-many relationships) model in Core Data.

Now let's say, I have an entity PlayList and an entity Song, and in PlayList an ordered to-many relationship to Song. This relationship has an inverse, and both have a nullify delete-rule.

I have remarked that when I delete a Song (let's call it gangnam) that belongs to a PlayList, this song is not removed from the relationship !! I tried to fix this with the following :

• I fixed the Apple's bug related to the to-many ordered relationships, using the excellent : KCOrderedAccessorFix. By the way, be careful if you use other solutions, because the bug is not only for the addAnObject part but also for the removeAnObject part. Result : much better but still not working : my relationship still refers to gangnam :(
• I tried : processPendingChanges : not working.

Now,

• If I save my context, the Song gangnam is removed.

So, my question is :

Do I have to save my context if I want to nullify the relationships ? Or am I missing something ?

I tried to reproduce the "bug" with a smaller model, but in this case, calling processPendingChanges is enough to nullify the relationship. So, if anyone has encountered the same problem/situation, I would be happy to know that I am not the only one to fight with Core Data ;)

解决方案

For a reason, the graph of the entities was not coherent (some bug of CoreData I guess, the relations and their inverse are not properly maintained). So, it refuses to delete the object. If I save, it first makes the graph coherent and then it is possible to remove the object.

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