Nhibernate one-to-many association - nhibernate

Question

I have such a simple model:
public abstract class Entity
{
public virtual Guid Id { get; protected set; }
}
public class Post : Entity
{
public String Title { get ; set; }
public String Content { get; set; }
public DateTime Timestamp { get; set; }
public Byte[] Thumbnail { get; set; }
}
public class Blog : Entity
{
public String Title { get; set; }
public ISet<Post> Posts { get; set; }
}
Then I have such mappings:
BLOG
<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" auto-import="true assembly="Application.Domain" namespace="Application.Domain.Entities">
<class name="Blog">
<!-- id generator -->
<id name="Id">
<generator class="guid.comb" />
</id>
<!-- properties/columns -->
<property name="Title" not-null="true" />
<!-- components/columns -->
<!-- associations -->
<set name="Posts" cascade="all">
<!-- key column? -->
</set>
</class>
</hibernate-mapping>
POST
<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" auto-import="true" assembly="Application.Domain" namespace="Application.Domain.Entities">
<class name="Blog">
<!-- id generator -->
<id name="Id">
<generator class="guid.comb" />
</id>
<!-- properties/columns -->
<property name="Title" not-null="true" />
<property name="Content" not-null="true" />
<property name="Timestamp" not-null="true"/>
<property name="Thmbnail" />
<!-- components/columns -->
<!-- associations -->
</class>
</hibernate-mapping>
How do I map one-to-many association (unidirectional)?
Thanks!

Answer 1

In the blog mapping file you need to define a one-to-many relation between the foreign key column that references the Blog entity in the post table say it is BlogId and you need to tell'em what class this one-to-many relation relates to, in your case this will be the Post class and you need to define it with it's fully qualified namespace that contains this class and a comma then the assembly name as following:
<set name="Posts" table="Post">
<key column="BlogId"/>
<one-to-many class="Application.Domain.Entities.Post, Application.Domain"/>
</set>

Answer 2

I think it's the same problem as described here.
And also, I think you have a mistake in mapping of the Post - class name shouldn't be Blog. Also, there's no relation from Post to Blog in your example.