To load by primary key, a unique single primary key must be defined on the table. Primary keys are automatically mapped. See Mapping Primary Keys for more information.
//Create a new Person to save to the database
Person person = new Person();person.FirstName =
"John";person.LastName =
"Smith";person.DateCreated =
DateTime.Now;
//Get the current instance of the helper
IDataHelper db = DataHelper.SessionFactory();
//Save it
db.Save(person);
//Load by primary key
Person personCopy = db.LoadByPrimaryKey<Person>(person.PersonId);