ADO.NET was designed to meet the needs of a new programming model: disconnected data architecture, tight integration with XML, common data representation with the ability to combine data from multiple and varied data sources, and optimized facilities for interacting with a database, all native to the .NET Framework.The ADO.NET DataSet is a memory-resident representation of data that provides a consistent relational programming model regardless of the source of the data it contains.
Datasets in Microsoft.Net - Creating Dataset at Design Time (Page 6 of 8 )
Right click on your project and add a new DataSet .xsd file to your project using the Add New Item dialog box.
Be sure to select the DataSet template in the dialog box rather than XML Schema. Selecting both item will add a new .xsd file to your project and launch the XML schema designer. However, DataSet schema files have an additional attribute set in their schema that Visual Studio .NET looks for to determine whether to treat the file as a standard XML schema or as a DataSet.
Once youíve added a new DataSet to your project, youíll see the same designer that you saw when we generated a DataSet based on DataAdapter objects, except that your new DataSet will be empty. Letís add a new DataTable to the Dataset. Next figure shows the shortcut (context) menu that appears when you right-click on the designer. Choose Add and then New Element from the shortcut menu to add a new DataTable to the DataSet. You can also choose the same command from the Schema menu.