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# save()

Saves the cache nodes.

```
func save() throws
```

## Discussion

You override this method to make persistent the necessary information from the cache nodes to the URL specified for the receiver.

### Special Considerations

You must override this method.

## See Also

[`-  updateCacheNode:fromManagedObject:`](/documentation/CoreData/NSAtomicStore/updateCacheNode(_:from:))

Updates the given cache node using the values in a given managed object.

[`-  willRemoveCacheNodes:`](/documentation/CoreData/NSAtomicStore/willRemoveCacheNodes(_:))

Method invoked before the store removes the given collection of cache nodes.

[`-  newReferenceObjectForManagedObject:`](/documentation/CoreData/NSAtomicStore/newReferenceObject(for:))

Returns a new reference object for a given managed object.


---

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