Fluent NHibernate Composite Mapping - nhibernate

Question

I am trying to map two tables :
the first one has an id (idA) and a field with the id (idB) of the other table.
the other one has a composite key based on the previous id (idB) and an other one (idB2)
The idea is that the second table contains the description of A split on multiple rows.
My current implementation is the following but I am unable to retrieve the partialDescription needed for concatenation.
How should I change my mapping to work? Any ideas? :)
public class A
{
long idA
lond idB
string fullDescription
}
public class B
{
long idB
long idB2
strind partialDescription
}
public class AMap : ClassMap<A>
{
public AMap()
{
Table("A");
Id(x => x.id).Column("idA").GeneratedBy.Native();
Map(x => x.idB).Column("idB")
HasMany(x => x.B).KeyColumn("idB").Inverse().Cascade.All().Not.LazyLoad();
}
}
public class BMap : ClassMap<B>
{
public BMap()
{
Table("B");
CompositeId()
.KeyReference(x => x.A, "idB")
.KeyProperty(x => x.idB2, "idB2");
Map(x => x.partialDescription, "desc").CustomType("AnsiString");
}
}

Answer 1

In fact, by your description, you must have this another scenario:
public class A
{
public virtual long Id { get; set; }
public virtual IList<B> PartialDescriptions { get; protected set; }
public string fullDescription
{
get
{
StringBuilder description = new StringBuilder();
foreach (var partial in PartialDescriptions)
{
description.Append(partial);
}
return description.ToString();
}
}
}
public class B
{
public virtual long Id { get; set; }
public virtual long Id2 { get; set; }
public virtual string Description { get; set; }
}
Then, try to implement your class maps like this:
public class BMap : ClassMap<B>
{
public BMap()
{
Table("B");
CompositeId()
.KeyReference(x => x.Id, "idB")
.KeyProperty(x => x.Id2, "idB2");
Map(x => x.partialDescription, "desc").CustomType("AnsiString");
}
}
public class AMap : ClassMap<A>
{
public AMap()
{
Table("A");
Id(x => x.Dd).Column("idA").GeneratedBy.Native();
HasMany(x => x.PartialDescriptions)
.KeyColumn("idB")
.Inverse()
.Cascade.All()
.Not.LazyLoad();
}
}
NOTE: I didn't tried to compile this code. I only expect that you can take the general .
I recommend you that take a look into Getting started section of Fluent NHibernate to more information.