After Releasing Application What to do If you want to Change the XcDatamodel?

I am developing an application for iPhone.

Som开发者_C百科etimes I change the xcdatamodel file.

Of course things will go wrong. But no problem. I just delete the application from the IPhone simulator and start a new again. I am developing after all.

Well, say I have 1 million subscribers with settings bookmark, etc.

Say I want to change the managed object model. Say I am updating my application. I can't just delete the old application and use a new one.

What should I do then at that time?

Is managed object model unchangeable after release?

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You can handle this using a Core Data Migration