NHibenate: Is there a way to create a one to many bidirectional relationship with composite keys?

[freshrebel]

I'm trying to setup a bidirectional relationship in NHibernate on 2 classes both with composite keys that overlap.

Another difficulty is that I can't just edit the SQL tables to for example add a proper ID.

This is probably an easy question but i can't find the answer anywhere.

I've got the HasMany down, as far as i can see. But I'm stuck with the HasOne. Also tried with Reference.

public class Parent

{

    public string A { get; set; }

    public string B { get; set; }

    public string C { get; set; }

    public List<Child> Children { get; set; }

    public string Data { get; set; }

}

public class Child

{

    public string A { get; set; }

    public string B { get; set; }

    public string C { get; set; }

    public string D { get; set; }

    public Parent Parent { get; set; }

    public string Data { get; set; }

}

public class ParentMap : ClassMap<Parent>

{

    public ParentMap()

    {

        CompositeId()

            .KeyProperty(x => x.A)

            .KeyProperty(x => x.B)

            .KeyProperty(x => x.C);

        Map(x => x.Data);

        HasMany(x => x.Children)

                .KeyColumn("A")

                .KeyColumn("B")

                .KeyColumn("C");

    }

}

public class ChildMap : ClassMap<Child>

{

    public ChildMap()

    {

        CompositeId()

            .KeyProperty(x => x.A)

            .KeyProperty(x => x.B)

            .KeyProperty(x => x.C)

            .KeyProperty(x => x.D);

        Map(x => x.Data);

        HasOne(x => x.Parent);

        // also tried

        //References<Parent>(x => x.Parent)

                //.Columns("A", "B", "C");

    }

}

The error i get now is: 

NHibernate.FKUnmatchingColumnsException: 'Foreign key (FK_3346D8AD:Child [C])) must have same number of columns as the referenced primary key (Parent [A, B, C])'

[freshrebel]

This error has been resolved with this code:

Though now I'm having a new error:

An invalid or incomplete configuration was used while creating a SessionFactory. Check PotentialReasons collection, and InnerException for more detail.

With this inner exception: Unable to build the insert statement for class Parent: a failure occured when adding the Id of the class

This inner exception has another inner exception: The column 'A' has already been added in this SQL builder Parameternaam: columnName

How can I manage this without changing the column name in the database?

Op maandag 15 juli 2019 18:15:59 UTC+2 schreef freshrebel: