What is the optimal way to remove an high number of objects ?

With Session.Remove() is entity data fetched in memory before removal? (probably a dumb question...)

Session.Remove(Query.All<MyEntity>().Where(e => e.ToRemove == true)):

Is there a more optimal way?

ReferentialIntegrityException during Remove

Is this a bug? Or should specify a special OnOwnerRemove action on my EntitySet so that when a "MyEntity" instance is removed all the links from and to this instance are removed too?

[HierarchyRoot]
  public class MyEntity : Entity
  {
    [Field, Key]
    public int Id { get; private set; }

    [Field, Association(PairTo = "Source")]
    public EntitySet<Link> LinksFromThis { get; private set; }

    [Field, Association(PairTo = "Destination")]
    public EntitySet<Link> LinksToThis { get; private set; }
  }

  [HierarchyRoot]
  public class Link : Entity
  {
    [Field, Key]
    public int Id { get; private set; }

    [Field]
    public MyEntity Source { get; set; }

    [Field]
    public MyEntity Destination { get; set; }
  }

using (Session.Open(domain))
      {
        using (var transactionScope = Transaction.Open())
        {
          // Creating new persistent object
          var myEntity1 = new MyEntity();
          var myEntity2 = new MyEntity();

          var link = new Link() { Source = myEntity1, Destination = myEntity2 };

          // Committing transaction
          transactionScope.Complete();
        }
      }

      // Reading all persisted objects from another Session
      using (Session session = Session.Open(domain))
      {
        using (var transactionScope = Transaction.Open())
        {
          session.Remove(Query.All<MyEntity>().Take(1));
          transactionScope.Complete();
        }
      }

Xtensive.Storage.ReferentialIntegrityException was unhandled
  Message=Referential integrity violation on attempt to remove 'TestDoRemove.Model.MyEntity', Key='MyEntity, (1)'.
  Source=Xtensive.Storage
  StackTrace:
       at Xtensive.Storage.ReferentialIntegrity.DenyActionProcessor.Process(RemovalContext context, AssociationInfo association, Entity removingObject, Entity target, Entity referencingObject, Entity referencedObject)
       at Xtensive.Storage.ReferentialIntegrity.RemovalProcessor.ProcessItems(IList`1 entities)
       at Xtensive.Storage.ReferentialIntegrity.RemovalProcessor.Remove(IEnumerable`1 entities)
       at Xtensive.Storage.Session.Remove[T](IEnumerable`1 entities)
       at TestDoRemove.Program.Main(String[] args)

Updated at 17.06.2010 7:58:52

Yes you are right : after a short reflexion I found that my attributes for the EntitySets should be like this:

[HierarchyRoot]
  public class MyEntity : Entity
  {
    [Field, Key]
    public int Id { get; private set; }

    [Field, Association(PairTo = "Source", OnOwnerRemove = OnRemoveAction.Cascade, OnTargetRemove = OnRemoveAction.Clear)]
    public EntitySet<Link> LinksFromThis { get; private set; }

    [Field, Association(PairTo = "Destination", OnOwnerRemove = OnRemoveAction.Cascade, OnTargetRemove = OnRemoveAction.Clear)]
    public EntitySet<Link> LinksToThis { get; private set; }
  }

This works like a charm : many thanks!

PS : maybe the exception message should be more explicit (but I don't know if that's feasible in all cases ;) )

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