FluentNHibernate this id not saving

Question

I'm starting my studies now with FluentNHibernate but found great difficulty. These are my objects:

public class Region
{
  public virtual Int64 Id { get; set; }
  public virtual string Name { get; set; }
  public virtual IList<City> ListCity { get; set; }
  public Region()
  {
   ListCity = new List<City>();
  }
 }
public class City
{
 public virtual Int64 Id { get; set; }
 public virtual string Name { get; set; }         
}

Here is the mapping:

public class RegionMap : ClassMap<Region>
{
        public RegionMap()
        {
            Table("tbRegion");
            Id(x => x.Id)
                .Column("Num_ID");
            Map(x => x.Name)
                .Column("Des_Name")
                .Not.Nullable();
            HasMany<City>(x => x.ListCity)
                .Inverse()
                .Cascade.SaveUpdate()
                .AsBag();

        }
    }

 public class CityMap : ClassMap<City>
    {
        public CityMap()
        {
            Table("tbCity");
            Id(x => x.Id)
                .Column("Num_ID");
            Map(x => x.Name)
                .Column("Des_City")
                .Not.Nullable();
        }
    }

So far I think it's alright. I used to own Hibernate to generate the database A simple code to test the mapping:

List<City> lcity = new List<City>();
lcity.Add(new City()
{
  Name = "Belo-Horizonte"
});
Region region = new Region()
{
    ListCity = lcity,
    Name = "Minas Gerais"
};
Repository.Connect(s => s.Save(region));

Look at my result

Num_ID Des_Name

1 Minas Gerais

Num_ID Des_City Region_id

1 Belo-Horizonte NULL

Why was not filled REGION_ID??

Thanks!

Answer 1

You have to teach it what to do with REGION_ID - your mapping doesn't say about it.

Not sure I get the idea what is it either - but looks like it a region foreign key in City table, so most probably you need to use something like this for RegionMap:

        HasMany<City>(x => x.ListCity)

            // Provide column key to reference by
            .KeyColumnNames.Add("REGION_ID")

            .Inverse()
            .Cascade.SaveUpdate()
            .AsBag();