Instance Property


A data token used to track client-side changes to records.


@property(nonatomic, copy) NSData *clientChangeTokenData;


When you modify records from a fetch operation, specify a client-generated data token using this property to indicate which version of the record you last modified. Compare the data token you supplied to the data token in the next record fetch to confirm the server has successfully received the device’s last modify request.

The default value is nil.

If you intend to change the value of this property, do so before executing the operation or submitting the operation object to a queue.

See Also

Configuring the Operation Object


The records to save to the database.


The IDs of the records to delete permanently from the database.


The policy to apply when the server contains a newer version of a specific record.


A Boolean value indicating whether the entire operation fails when one or more records in the same zone cannot be written.

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