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Tracking a familial relationship in Core Data (1 parent entity + 2 types of children, one of which is recursive), trying to create a drop-menu in Interface Builder that lists the names of the parent entities so that the user can choose one to associate as the parent of the entry being edited. I've got the bindings all set, but when it runs it produces the following error text in the first slot of the menu:
Relationship fault for (
<NSRelationshipDescription: 0x100143ed0>), name parent, isOptional 1, isTransient 0, entity Family, renamingIdentifier parent, validation predicates (), warnings (), versionHashModifier (null), destination entity Family, inverseRelationship subFamilies, minCount 0, maxCount 0 on 0x10025c850
I've done a little bit of reading around online, and it appears to have to do with the fact that I've got a many-to-one relationship set up (as one parent can have multiple children, but I want to limit each child to only one parent). I've been trying to figure out a way to restructure the data model to not put a many-to-one relationship on something that'll need to be called up in such a fashion, but I'm getting stuck trying to figure out how to track the children. Any ideas on possible methods of resolving the issue?
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From the moment we ask for the value of a property of one of the records, Core Data jumps into action and fetches the data from the persistent store. This is better known as firing a Core Data fault.
Inverse relationships enable Core Data to propagate change in both directions when an instance of either the source or destination type changes. Every relationship must have an inverse. When creating relationships in the Graph editor, you add inverse relationships between entities in a single step.
Core Data is a framework that you use to manage the model layer objects in your application. It provides generalized and automated solutions to common tasks associated with object life cycle and object graph management, including persistence.
Core Data is designed to work in a multithreaded environment. However, not every object under the Core Data framework is thread safe. To use Core Data in a multithreaded environment, ensure that: Managed object contexts are bound to the thread (queue) that they are associated with upon initialization.
A fault in Core Data is not an error, it just means that the what you are trying to access hasn't been retrieved from the database yet. If you do something like [fetchResults valueForKey:@"name"] it will fire and you should get what you expect. It shouldn't be a problem with your relationship model.
By the way, "minCount 0, maxCount 0" seems weird. Is that really what you want? minCount of 0 and maxCount of 1 should make more sense.
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