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# CKSyncEngineEventType

Describes an event that occurs during a sync operation.

```
enum CKSyncEngineEventType
```

## Topics

### Event types

[`CKSyncEngineEventType.stateUpdate`](/documentation/CloudKit/CKSyncEngineEventType/stateUpdate)

The sync engine updated its state.

[`CKSyncEngineEventType.accountChange`](/documentation/CloudKit/CKSyncEngineEventType/accountChange)

The user signed in or out of their account.

[`CKSyncEngineEventType.fetchedDatabaseChanges`](/documentation/CloudKit/CKSyncEngineEventType/fetchedDatabaseChanges)

The sync engine has fetched new database changes from the server.

[`CKSyncEngineEventType.fetchedRecordZoneChanges`](/documentation/CloudKit/CKSyncEngineEventType/fetchedRecordZoneChanges)

The sync engine fetched new record zone changes from the server.

[`CKSyncEngineEventType.sentDatabaseChanges`](/documentation/CloudKit/CKSyncEngineEventType/sentDatabaseChanges)

The sync engine sent a batch of database changes to the server.

[`CKSyncEngineEventType.sentRecordZoneChanges`](/documentation/CloudKit/CKSyncEngineEventType/sentRecordZoneChanges)

The sync engine sent a batch of record zone changes to the server.

[`CKSyncEngineEventType.willFetchChanges`](/documentation/CloudKit/CKSyncEngineEventType/willFetchChanges)

The sync engine is about to fetch changes from the server.

[`CKSyncEngineEventType.willFetchRecordZoneChanges`](/documentation/CloudKit/CKSyncEngineEventType/willFetchRecordZoneChanges)

The sync engine is about to fetch record zone changes from the server for a specific zone.

[`CKSyncEngineEventType.didFetchRecordZoneChanges`](/documentation/CloudKit/CKSyncEngineEventType/didFetchRecordZoneChanges)

The sync engine has completed fetching record zone changes from the server for a specific zone.

[`CKSyncEngineEventType.didFetchChanges`](/documentation/CloudKit/CKSyncEngineEventType/didFetchChanges)

The sync engine finished fetching changes from the server.

[`CKSyncEngineEventType.willSendChanges`](/documentation/CloudKit/CKSyncEngineEventType/willSendChanges)

The sync engine is about to send changes to the server.

[`CKSyncEngineEventType.didSendChanges`](/documentation/CloudKit/CKSyncEngineEventType/didSendChanges)

The sync engine finished sending changes to the server.


---

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