Core Data not-reverse relationship subquery

Posted by user561485 on Stack Overflow See other posts from Stack Overflow or by user561485
Published on 2011-01-03T16:52:05Z Indexed on 2011/01/03 16:53 UTC
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objective-c

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core-data

Hi,

I have the following entities in CoreData:

Village - villageID

Bookmark - (relation) village

There are multiple villages with each an unique villageID. I have a entity Bookmark which only has a relation to a Village entity; it isn't possible to make a reverse relation.

Now I would like to get the village entities where there exists a Bookmark relation. I've red something about subqueries, but I can't get it right for this situation.

It must be something like: Village.villageID IN (Bookmark.village.villageID)

It isn't possible to get first all the Bookmarks and then loop to get all the Villages, because of the design of the framework.

Can this be done in CoreData (I presume the answer is "Yes, of course!") and how?

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