Join table on custom columns - nhibernate

Question

I want to join table based NOT on their Database-level relationship (PK, FK), but some custom criteria:
SELECT * FROM Users u inner join Docs d on u.Doc = d.ISBN
and map it to
public class User
{
public Doc Document { get; set; }
}
public class Doc
{
public Int64 Id {get; protected set}
public Int64 Isbn {get; set}
}
Is it possible with only mappings or do I need to call some method on Criteria API (which I use)?
I have tried the following:
public class UserMap : ClassMapping<User>
{
public UserMap()
{
Table("Users");
Id(x => x.Id, p => p.Column("Id"););
ManyToOne(x => x.Document, m =>
{
m.Column("Doc");
m.ForeignKey("ISBN");
m.Fetch(FetchKind.Join);
m.Access(Accessor.Property);
m.Lazy(LazyRelation.NoLazy);
m.NotNullable(true);
});
}
}
public class DocMap : ClassMapping<Doc>
{
public DocMap()
{
Table("Docs");
Id(x => x.Id, p =>
{
p.Column("Id");
p.Generator(Generators.GuidComb);
});
Property(x => x.Isbn, p =>
{
p.Column("ISBN");
p.NotNullable(true);
});
}
}
//2.Criteria API
var criteria = Session.CreateCriteria("User")
// ...
criteria.CreateCriteria("Document", "Docs", JoinType.InnerJoin, docCriterion);
but the result is:
SELECT * FROM Users u
inner join Docs d on u.Doc=d.Id /* docCriterion */
left outer join Docs d2 on u.Doc=d.Id

Answer 1

try this
criteria.CreateCriteria("Users")
.CreateCriteria("Document").Add(Restrictions.Eq("Isbn ", ?);
in your query u.Doc = d.ISBN is not correct, cause Doc is Doc entity and ISBN is number