One of the biggest complaints about typed datasets (and untyped ones as well) is that when you serialize them (i.e.: convert them to XML to be transferred to a web service), they always emit the schema definition. This results in excess data being transferred when it really is not necessary. A new improvement in .NET 2.0 is the ability to set the SchemaSerializationMode property on the DataSet object. By setting this to SchemaSerializationMode.ExcludeSchema, the DataSet will not output the xml schema, just the data.
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