Is there an difference between transient properties defined in the data model, or in the custom subc

Posted by mystify on Stack Overflow See other posts from Stack Overflow or by mystify
Published on 2010-06-08T09:38:54Z Indexed on 2010/06/08 9:42 UTC
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iphone

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core-data

I was reading that setting the value of a transient property always results in marking the managed object as "dirty". However, what I don't get is this: If I make a subclass of NSManagedObject and use some extra properties which I don't need to be persistet, how does Core Data know about them and how can it mark the object as dirty when I access these?

Again, they're not defined in the data model, so Core Data has no really good hint that they are there.

Or does Core Data use some kind of introspection to analyze my custom class and figure out what properties I have in there?

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