DataSet ds = LoadDataSetUsingDataAdapter();

var highDiscountOrders =
from o in ds.Tables["OrderDetails"].AsEnumerable()
where o.Field<float?>("Discount") > 0.2
select o;

DataTable highDiscountOrdersTable = highDiscountOrders.CopyToDataTable();
highDiscountOrdersTable.TableName = "HighDiscountOrders";
ds.Tables.Add(highDiscountOrdersTable);
