In a Core Data project using the 10.5 SDK, I've written several mapping models that have worked, but now going from version 4 to 5, it "just doesn't work". Compiles OK, but opening an old document results in a Cocoa Error Domain code 134140 "Can't find mapping model for migration". From experience, I believe that this more likely means that the model was found in the package but it didn't succesfully migrate all entities/properties.
I suspect the problem is that I've been skating by without knowing what I'm doing. I step through all the Entity Mappings and fill in a Value Expression for any Property Mappings that are blank. Is that the basic approach? In my latest model revision, I added a relationship between existing entities. The value of nil would be fine, so I typed 'nil' in for "Value Expression" on each end. The compiler swallowed it OK. Also, I added a Date attribute, which I would like to default to NSDistantFuture, but since I didn't know how to enter that, I entered 'nil' there also. Should these entries work? Is there any documentation which defines the syntax to be used for "Value Expression"? The two paragraphs at the bottom of this page [1] show a simple example but not much detail. Is there any identification of the failing property included in error 134140? It looks like just a description of the Managed Object Model. Thanks! Jerry Krinock 1. http://developer.apple.com/Mac/library/documentation/Cocoa/Conceptual/CoreDataVersioning/Articles/vmMappingOverview.html _______________________________________________ Cocoa-dev mailing list ([email protected]) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to [email protected]
