[Option] Auto [Description] 
This is the default. Examines the XML and chooses the most appropriate option in the following order: If the XML is a DiffGram, DiffGram is used. If the DataSet contains a schema or the XML contains an inline schema, ReadSchema is used. If the DataSet does not contain a schema and the XML does not contain an inline schema, InferSchema is used. If you know the format of the XML being read, for best performance it is recommended that you set an explicit XmlReadMode, rather than accept the Auto default.