Question

I’ve defined the primary key as following:

CompositeId()
    .KeyProperty(x => x.Id)
    .KeyProperty(x => x.Type);

I’ve tried the following:

References(x => x.EntityWith2ColsPK);

And failed with:

Foreign key (Fk_MyEntity_EntityWith2ColsPK:MyEntities [Fk_EntityWith2ColsPK])) must have same number of columns as the referenced primary key (EntityWith2ColsPKs [Id, Type])

How can I reference EntityWith2ColsPK from another entity?

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Update:

I’ve tried the following (according to AlfeG’s comment):

HasMany<EntityWith2ColsPK>(x => x.EntityWith2ColsPK).KeyColumns.Add("Id", "Type").Cascade.All();

Which failed with:

Custom type does not implement UserCollectionType: EntityWith2ColsPK

But anyway I don’t want a 1 to many relation, I want a 1 to 1 relation. Still, I can’t make either of them work.

Also, I’ve tried:

HasOne<EntityWith2ColsPK>(x => x.EntityWith2ColsPK).PropertyRef(x => x.Id).PropertyRef(x => x.Type);

Which fails with:

NHibernate.MappingException : property not found: Type on entity EntityWith2ColsPK

What can I do for this to really work?

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I managed to achieve something in the db.. but yet, for some reason I suspect it maps the property “Type” twice, because I want it to be both part of the Primary Key, and part of the Foreign Key..
This is what I did:

References(x => x.EntityWith2ColsPK).Columns("EntityWith2ColsPKId", "Type").Formula("Id = :EntityWith2ColsPKId AND Type = :Type");

But I received the following exception:

System.IndexOutOfRangeException : Invalid index 8 for this SqlParameterCollection with Count=8.

Because the mapping of this entity is same as EntityWith2ColsPK:

CompositeId()
    .KeyProperty(x => x.Id)
    .KeyProperty(x => ((ILocalizedEntity) x).Language);

HELP!

Answer 1

You can use something like this since you aren’t using cascade anyway on your Reference

References(x => x.EntityWith2ColsPK)
    .Columns(new string[] { "ID", "TYPE" })
    .Not.Update()
    .Not.Insert();