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# NSManagedObjectContext.DidMergeChangesMessage

Posted after a main queue context merges changes from another context, containing object IDs.

```
struct DidMergeChangesMessage
```

## Overview

Only use this message type for contexts with `NSMainQueueConcurrencyType`.
For private queue contexts, use [`NSManagedObjectContext.DidMergeChangesAsyncMessage`](/documentation/CoreData/NSManagedObjectContext/DidMergeChangesAsyncMessage).

## Topics

### Instance Properties

[`let context: NSManagedObjectContext`](/documentation/CoreData/NSManagedObjectContext/DidMergeChangesMessage/context)

[`let deletedIDs: Set<NSManagedObjectID>`](/documentation/CoreData/NSManagedObjectContext/DidMergeChangesMessage/deletedIDs)

Object IDs of objects that were deleted during the merge.

[`let historyToken: NSPersistentHistoryToken?`](/documentation/CoreData/NSManagedObjectContext/DidMergeChangesMessage/historyToken)

The persistent history token representing the state after the merge.

[`let insertedIDs: Set<NSManagedObjectID>`](/documentation/CoreData/NSManagedObjectContext/DidMergeChangesMessage/insertedIDs)

Object IDs of objects that were inserted during the merge.

[`let invalidatedIDs: Set<NSManagedObjectID>`](/documentation/CoreData/NSManagedObjectContext/DidMergeChangesMessage/invalidatedIDs)

Object IDs of objects that were invalidated during the merge.

[`let queryGeneration: NSQueryGenerationToken?`](/documentation/CoreData/NSManagedObjectContext/DidMergeChangesMessage/queryGeneration)

Query generation token after the merge.

[`let refreshedIDs: Set<NSManagedObjectID>`](/documentation/CoreData/NSManagedObjectContext/DidMergeChangesMessage/refreshedIDs)

Object IDs of objects that were refreshed during the merge.

[`let updatedIDs: Set<NSManagedObjectID>`](/documentation/CoreData/NSManagedObjectContext/DidMergeChangesMessage/updatedIDs)

Object IDs of objects that were updated during the merge.

## Relationships

### Conforms To

[`MainActorMessage`](/documentation/Foundation/NotificationCenter/MainActorMessage)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

---

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