Core data property not updating
It's created for exactly this purpose, you don't have to explicitly analyze each difference between how the old and new entity is defined - that's what it does.
If the latter, then unless there's a good reason I'd probably suggest the purge approach.
Please upload a small complete test project with the corresponding DDL/DML script to ftp://ftp.(credentials: anonymous / your Email).
Help Articles We cannot reproduce the issue at the moment.
Manifests are only good for small and manageable updates.
If you're going to have many 1000s of records, what is the advantage over analyzing those records if the incoming data is the single source of truth anyway?
The deleting would purge all data Are you worried about resource usage, about there being a gap with no data available, or are you worried about the time between requesting data and new data appearing? I worked on a project that ingested 2MB of JSON and saved it to the CD database in like 20 seconds on an i Pad 1.
We store the manifest in Core Data for easy access throughout the app, and we only bother fetching the latest manifest when its "version" property does not match the client's (in other words, we only update the manifest when it changes, not every app session).
I'm on the fence about the best way of implementing the Core Data updating.
I recommend you choosing only one approach (from my experience fluent api is usually better - more extensible for future and persistence models look much cleaner) and try to go without specifying that the Id should or should not change because without it you will get what you want.
In this chapter, you will learn how to save a disconnected entity which is not being tracked by a context in EF 6.