[fluent-nhib] Mapping multiple objects to single lookup table

[CodeMonkey]

Hi all

I am struggling a little in getting my mapping right.

What I have is a single self joined table of look up values of certain
types. Each lookup can have a parent, which can be of a different
type.

For simplicities sake lets take the Country and State example.

So the lookup table would look like this:

Lookups
  Id
  Key
  Value
  LookupType
  ParentId - self joining to Id


base class

public class Lookup : BaseEntity
    {
        public Lookup() {}

        public Lookup(string key, string value)
        {
            Key = key;
            Value = value;
        }

        public virtual Lookup Parent { get; set; }

        [DomainSignature]
        [NotNullNotEmpty]
        public virtual LookupType LookupType { get; set; }

        [NotNullNotEmpty]
        public virtual string Key { get; set; }

        [NotNullNotEmpty]
        public virtual string Value { get; set; }
    }

The lookup map

    public class LookupMap : IAutoMappingOverride<DBLookup>
        {
            public void Override(AutoMapping<Lookup> map)
            {
                map.Table("Lookups");
                map.References(x => x.Parent,
"ParentId").ForeignKey("Id");
 
map.DiscriminateSubClassesOnColumn<string>("LookupType").CustomType(typeof(LookupType));

            }
        }


BASE SubClass map for subclasses

public class BaseLookupMap<T> : SubclassMap<T> where T : DBLookup
    {

        protected BaseLookupMap()
        {
        }

        protected BaseLookupMap(LookupType lookupType)
        {
            DiscriminatorValue(lookupType);
            Table("Lookups");
        }
    }


Example subclass map



    public class StateMap : BaseLookupMap<State>
        {
            protected StateMap() : base(LookupType.State) { }
        }

Now I've *almost* got my mappings set, however the mapping is still
expecting a table-per-class setup, so is expecting a 'State' table to
exist with a reference to the states Id in the Lookup table.

I hope this makes sense.

This doesn't seem like an uncommon approach when wanting to keep
lookup-type values configurable.

Thanks in advance.

Al

-- 
You received this message because you are subscribed to the Google Groups 
"Fluent NHibernate" group.
To post to this group, send email to fluent-nhibern...@googlegroups.com.
To unsubscribe from this group, send email to 
fluent-nhibernate+unsubscr...@googlegroups.com.
For more options, visit this group at 
http://groups.google.com/group/fluent-nhibernate?hl=en.