You have a Customer table with fields of LastName and FirstName, and want to use Silverlight DataGrid to display all the records. To implement this, You can use N-tier application architect.
1. The N-Tier Silverlight application consists of following layers: Data Entity, Data Access, Business, WCF Service and Silverlight Client.
2. At data entity layer, build the class of Customer with properties of LastName and FirstName.
3. At data access layer, build the method of GetCustomers.
4. At business layer, build the method of GetCustomers. It is just a pass-through method from the data access layer because no business rule is involved here.
5. At WCF service layer, build the method (a service operation) of GetCustomers. It is just a pass-through method from the business layer because no business rule is involved here.
6. At Silverlight Client layer, create Customer XAML page, and add Customer DataGrid.
7. At Silverlight Client layer, in the Customer XAML code behind, build a procedure of GetCustomers, which is an asynchronous call to the WCF Service. And pass the result to ItemsSource of the Customer DataGrid.