RAD Studio |  |

Updating Records
See Also
Collapse All

The contents of the change log are stored as a data packet in the client dataset's Delta property. 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 client dataset's Delta property to the (internal or external) provider. Delta is a data packet that contains a client dataset's updated, inserted, and deleted records.
2. The provider applies the updates, caching any problem records that it can't 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

Overview of Using Cached Updates

Indicating What Records Are Modified

Choosing the Type of Dataset for Caching Updates

Copyright(C) 2009 Embarcadero Technologies, Inc. All Rights Reserved.
What do you think about this topic? Send feedback!