after I insert a ManagedObject into a context I'd like to fetch it later but before saving the context (I'd save after all objects are inserted). It appears that querying the context later with a fetch concerning those objects returns nothing if the context wasn't previously saved. Is there a way to save only in the end ?(I guess i can save my objects in an array or dictionary and query that but i thought coredata would do this for me)
Try this:
[myFetchRequest setIncludesPendingChanges:YES];
From the documentation:
Sets if, when the fetch is executed, it matches against currently unsaved changes in the managed object context.
来源:https://stackoverflow.com/questions/3235498/coredata-fetching-an-object-from-an-unsaved-context