Working with DiffGrams

A DiffGram is an XML document that is used to identify current and original versions of data elements. Because a DiffGram can be defined to contain only modified data rows, it is the most efficient means of transferring DataSet objects for the purpose of updating a remote data store. In fact, the DataSet internally uses DiffGrams to load and persist its contents, and to serialize its contents for transport.

A DataSet can be written as a DiffGram by specifying a value of XmlWriteMode::DiffGram when calling the DataSet::WriteXml method. When this is done, the resulting XML file is populated with all the necessary information to accurately recreate the contents, though not the schema, of the DataSet, including column values ...

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