Updating Records

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Go Up to Using a Client Dataset to Cache Updates

The contents of the change log are stored as a data packet in the Delta property of the client dataset. To make the changes in Delta permanent, the client dataset must apply them to the database (or source dataset or XML document).

When a client applies updates to the server, the following steps occur:

  1. The client application calls the ApplyUpdates method of a client dataset object. This method passes the contents of the Delta property of the client dataset to the (internal or external) provider. Delta is a data packet that contains a updated of the client dataset, inserted, and deleted records.
  2. The provider applies the updates, caching any problem records that it cannot resolve itself. See Responding to client update requests for details on how the provider applies updates.
  3. The provider returns all unresolved records to the client dataset in a Result data packet. The Result data packet contains all records that were not updated. It also contains error information, such as error messages and error codes.
  4. The client dataset attempts to reconcile update errors returned in the Result data packet on a record-by-record basis.


See Also