Question

I think I’m misunderstanding something about how this works. This is my fluent mapping:

public class FunctionInfoMap : ClassMap<FunctionInfo>
 {
  public FunctionInfoMap()
  {
   Id(x => x.Id);
   Map(x => x.Name);
   Map(x => x.Signature);
   Map(x => x.IsNative);
   Map(x => x.ClassId);
   References(x => x.Class, "ClassId");
   HasMany(x => x.CallsAsParent).Inverse();
   HasMany(x => x.CallsAsChild).Inverse();
   Table("Functions");
  }
 }

 public class CallMap : ClassMap<Call>
 {
  public CallMap()
  {
   CompositeId()
    .KeyProperty(x => x.ThreadId)
    .KeyProperty(x => x.ParentId)
    .KeyProperty(x => x.ChildId)
    .Mapped();
   Map(x => x.ThreadId).Index("Calls_ThreadIndex");
   Map(x => x.ParentId).Index("Calls_ParentIndex");
   Map(x => x.ChildId).Index("Calls_ChildIndex");
   Map(x => x.HitCount);
   References(x => x.Thread, "ThreadId");
   References(x => x.Parent, "ParentId");
   References(x => x.Child, "ChildId");
   Table("Calls");
  }
 }

 public class SampleMap : ClassMap<Sample>
 {
  public SampleMap()
  {
   CompositeId()
    .KeyProperty(x => x.ThreadId)
    .KeyProperty(x => x.FunctionId)
    .Mapped();
   Map(x => x.ThreadId);
   Map(x => x.FunctionId);
   Map(x => x.HitCount);
   References(x => x.Thread, "ThreadId");
   References(x => x.Function, "FunctionId");
   Table("Samples");
  }
 }

Now when I create this schema into a fresh database, that FunctionId field from SampleMap winds up in the Calls table.

create table Calls (
        ThreadId INTEGER not null,
       ParentId INTEGER not null,
       ChildId INTEGER not null,
       HitCount INTEGER,
       FunctionId INTEGER,
       primary key (ThreadId, ParentId, ChildId)
    )

create table Samples (
    ThreadId INTEGER not null,
   FunctionId INTEGER not null,
   HitCount INTEGER,
   FunctionId INTEGER,
   primary key (ThreadId, FunctionId)
)

I don’t understand why it’s there, since it should only exist in the Samples table.

Answer 1

I finally figured out the problem, more or less. The pair of collections on FunctionInfoMap were confusing NHibernate, since they don’t actually lead anywhere. Adding KeyColumn entries to link them up to the Parent and Child associations corrected the stray field.