use Silverlight 4 and attach the database using
using (var connection = new ComToolkit.Data.AdoConnection(connectionString))
{
connection.Open();
var command = connection.CreateCommand();
command.CommandText = "SELECT MyColumn FROM MyTable";
var reader = command.ExecuteReader();
while (reader.Read())
{
object byindex = reader[0];
object bystring = reader["MyColumn"];
}
}