I'm trying to share a table of simple elements between to different objects, but getting a foreign key constraint added when I generate the schema that is causing errors.
Here's a summary of what I'm trying to do:
Object A has a collection of decimals
Object B has a collection of decimals
Both decimal collections point to a shared table.
However the schema generation adds foreign key constraints for tables A and B, so that whenever I insert something it clashes with the foreign key for the other object.
I've worked round it by using separate tables, but these are proliferating, so I'd quite like to be able to use a single table for all.
Here's a contrived example that runs as a console app to show what I mean:
Code:
public class FirstClass
{
public FirstClass() { }
public Guid Id;
public IList<decimal> Numbers = new List<decimal>();
}
public class SecondClass
{
public SecondClass() { }
public Guid Id;
public IList<decimal> Numbers = new List<decimal>();
}
class Program
{
static void Main(string[] args)
{
//Create Schema
NHibernate.Cfg.Configuration cfg = new NHibernate.Cfg.Configuration();
cfg.AddAssembly(System.Reflection.Assembly.GetExecutingAssembly());
NHibernate.Tool.hbm2ddl.SchemaExport se = new NHibernate.Tool.hbm2ddl.SchemaExport(cfg);
se.SetOutputFile(Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "schema.sql"));
se.Execute(true, true, false, true);
//Save one of each class
using (ISessionFactory sessionFactory = cfg.BuildSessionFactory())
{
using (ISession session = sessionFactory.OpenSession())
{
FirstClass first = new FirstClass();
first.Numbers.Add(1.0M);
SecondClass second = new SecondClass();
second.Numbers.Add(2.0M);
session.Save(first);
session.Save(second);
try
{
session.Flush();
}
catch (Exception ex)
{
Console.WriteLine(ex.ToString());
}
}
}
}
}
And mapping:
Code:
<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" namespace="NHListTest" assembly="NHListTest" default-lazy="false">
<class name="FirstClass" table="FirstClass">
<id name="Id" unsaved-value="00000000-0000-0000-0000-000000000000" access="field">
<generator class="guid.comb">
</generator>
</id>
<list name="Numbers" generic="true" table="Numbers" access="field">
<key column="ParentId" />
<index column="idx" />
<element type="Decimal" column="Value" />
</list>
</class>
<class name="SecondClass" table="SecondClass">
<id name="Id" unsaved-value="00000000-0000-0000-0000-000000000000" access="field">
<generator class="guid.comb">
</generator>
</id>
<list name="Numbers" generic="true" table="Numbers" access="field">
<key column="ParentId" />
<index column="idx" />
<element type="Decimal" column="Value" />
</list>
</class>
</hibernate-mapping>
I'm hoping there's just something I've missed from the mapping file to allow it. Thanks in advance for any help.
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