Many to one example 3 of 4

<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" namespace="TstDBConnection.Entities" assembly="TstDBConnection">
  <class name="Tree" table="Tree">
    <id name="Id" column="Id">
      <generator class="guid.comb"/>
    </id>
    <property name="Name" column="Name"></property>
  </class>
</hibernate-mapping>

<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" namespace="TstDBConnection.Entities" assembly="TstDBConnection">
  <class name="Leaf" table="Leaf">
    <id name="Id" column="Id">
      <generator class="guid.comb"/>
    </id>
    <property name="Name" column="Name"></property>
    <many-to-one name="Tree" class="Tree" column="TreeId" cascade="save-update" />
  </class>
</hibernate-mapping>

namespace TstDBConnection.Entities
{
    public class Tree
    {
        public virtual Guid Id { get; set; }
        public virtual string Name { get; set; }
    }
}

namespace TstDBConnection.Entities
{
    public class Leaf
    {
        public virtual Guid Id { get; set; }
        public virtual string Name { get; set; }
        public virtual Tree Tree { get; set; }
    }
}

        public static void TestMany2One(ISessionFactory sessionFactory)
        {
            using (ISession session = sessionFactory.OpenSession())
            {
                Tree tree = new Tree() { Name = "Big Tree" };
                Leaf leaf = new Leaf() { Tree = tree, Name = "Leaf A for Big Tree" };
                session.Save(leaf);
                session.Flush();

                var query = from leafT in session.Query<Leaf>() select leafT;
                IList<Leaf> employees = query.ToList();
            }
        }

        static void Main(string[] args)
        {
            log4net.Config.XmlConfigurator.Configure(); // log4net
            Configuration configuration = new Configuration();
            configuration.Configure();
            ISessionFactory sessionFactory = configuration.BuildSessionFactory();

            TestMany2One(sessionFactory);

            sessionFactory.Close();
        }