Fluent NHibernate Bidirectional HasMany Mapping leaving orphaned records

Question

I am having an issue and cant seem to figure out what I am doing wrong. I have a company that has many groups, a group has many users, and a user belongs to a group. Adding a group to a company works fine, however I am not able to add a user to a group.

here is my mapping:

  public GroupMapping()
  {
     Id(x => x.Id);
     Map(x => x.Name);

     References(x => x.Company).Column("Company_Id");

     HasMany(x => x.Users)
        .Table("User")
        .KeyColumn("Group_Id")
        .Cascade.None();
  }

  public UserMapping()
  {
     Id(x => x.Id);

     References(x => x.Group).Column("Group_Id");

     HasMany(x => x.Role)
        .KeyColumn("User_Id")
        .Cascade.All();
  }

On the database I have the FK set to Not Null. The Key is on the User Table called Group_Id. I am assigning my user to the group using the following method:

  public JsonResult AssignGroup(int id, int groupId)
  {
     var user = UserRepository.GetById(id);
     var group = GroupRepository.GetById(groupId);

     user.Group = group;

     UserRepository.Save(user);

     return Json(new {});
  }

I do not receive any errors, however the Group_Id is never set. Any help would be appreciated!

Thanks, Joe

Answer 1

• HasMany(x => x.Users) is missing an Inverse() otherwise it throws when you add a user. Only the User should maintain the FK
• you most probably are missing session.Flush() or transaction.Commit(); in your repository method