Join multiple tables with NHibernate and QueryOver

Question

I have this tables:

Person -> PersonFavorites, PersonCompany
PersonCompany -> Company

I have now to do the following select with NHibernate and QueryOver:

select * from Person 
  inner join PersonFavorites on Person.Id = PersonFavorites.PersonId 
  inner join PersonCompany on Person.Id = PersonCompany.PersonId 
  inner join Company on Company.Id = PersonCompany.CompanyId
where ...

Can someone give me a sample, how I can do that? - My Problem is, that I have to join multiple Tables Person -> PersonCompany -> Company. The Join Person -> PersonCompany and Person -> PersonFavorites are no problem - but the next step from PersonCompany -> Company.

Answer 1

Mapping should be similar to the following:

Entities

class Person
{
    Collection<PersonFavorites> favorites;
    Collection<PersonCompany> companies;
}

class PersonFavorite
{
    Person person;
    Favorite favorite;
}

class PersonCompany
{
    Person person;
    Company company;
}

Query

Person personAlias = null;
PersonFavorites personfavouriteAlias = null;
PersonCompany personCompanyAlias  = null;
Company companyAlias = null;
Favorite favouriteAlias = null;

var query = Session.QueryOver<Person>(() => personAlias)
    .joinAlias(() => personAlias.favorites, () => personfavouriteAlias)
    .joinAlias(() => personAlias.companies, () => personCompanyAlias)
    .joinAlias(() => personfavouriteAlias.Favourite, () => favouriteAlias)
    .joinAlias(() => personCompanyAlias.Company, () => companyAlias)