many-to-many mapping in NHibernate

Question

I\'m looking to create a many to many relationship using NHibernate. I\'m not sure how to map these in the XML files. I have not created the classes yet, but they will jus

Answer 1

You can put the many-to-many relation to either class, or even to both. This is up to your domain model. If you map it to both, one of them is inverse.

class Person
{
  // id ...
  IList Competencies { get; private set; }

  // you domain model is responsible to manage bidirectional dependencies.
  // of course this is not a complete implementation
  public void AddCompetency(Competency competency)
  {
    Competencies.Add(competency);
    competency.AddPerson(this);
  }
}

class Competency
{
  // id ...
  IList Persons { get; private set; }
}

Mapping:

Only make it bidirectional if you really need it.

By the way: it is much better to write the classes first and create the database design afterwards. The database can be exported from the mapping files. This is very useful.