No Cascade Delete-Orphan option?

[James Crowley]

I'm probably missing something blindingly obvious here, but is there
any reason why there is no delete-orphan option when setting the
cascade types?

Thanks

James

[Mikael Henriksson]

.I believe what you are looking for is Cascade.AllDeleteOrphan()

[James Crowley]

Hi Mikael,

thanks for the response. Unfortunately, that's the "all-delete-orphan"
option (which I'd normally use), but I need the "delete-orphan" option
(so it doesn't automatically persist inserts and updates). I'm having
to do a slightly nasty workaround as described here:
http://fgheysels.blogspot.com/2009/05/forcing-nhibernate-to-cascade-deletes.html

in order to be able to delete and then insert entities on a collection
with a unique constraint (that's not on its primary key).

Unless you have any suggestions on how else I might achieve this?

Many thanks,

James

2009/9/3 Mikael Henriksson <mik...@zoolutions.se>:

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James Crowley
Managing Director
Developer Fusion - Connecting developers worldwide

Developer Fusion Ltd | 58 Sandringham Close | Enfield, EN1 3JH
mob: 07986 624128 web: http://www.developerfusion.com/

[Mikael Henriksson]

As far as the NHibernate reference is concerned there is no cascade "delete-all-orphans" maybe cascade "delete" is the one you are after? Cascade.Delete() in fluent. If it's not supported in nhibernate it's not going to be supported in Fluent either.

[Hudson Akridge]

Mike is correct

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- Hudson
http://www.bestguesstheory.com
http://twitter.com/HudsonAkridge

[James Crowley]

Hmm, I'm even more confused now!

Ayende makes reference to this way back in 2006:

http://ayende.com/Blog/archive/2006/12/02/NHibernateCascadesTheDifferentBetweenAllAlldeleteorphansAndSaveupdate.aspx

??

Thanks

James

2009/9/4 Hudson Akridge <hudson....@gmail.com>:

[Stuart Childs]

Well, looking back as far as the 1.0.2 documentation, only the
following cascades are documented:

cascade="all|none|save-update|delete|all-delete-orphan"

I also found this comment from January 14: "Hmm.. I'm using NHibernate
2.2 and this happens: [MappingException: Unsupported cascade style:
delete-orphans]"
(here: http://stackoverflow.com/questions/444753/how-do-i-make-nhibernate-delete-child-refererences-when-i-delete-a-parent)

Now I suppose it's possible that they slipped in a delete-orphans
cascade and didn't tell anyone but I'd have to check the NH source to
find out.

[Stuart Childs]

I just looked and here is the full cascade dictionary for NH 2.1 GA:
static CascadeStyle()
{
Styles["all"] = All;
Styles["all-delete-orphan"] = AllDeleteOrphan;
Styles["save-update"] = Update;
Styles["persist"] = Persist;
Styles["merge"] = Merge;
Styles["lock"] = Lock;
Styles["refresh"] = Refresh;
Styles["replicate"] = Replicate;
Styles["evict"] = Evict;
Styles["delete"] = Delete;
Styles["remove"] = Delete; // adds remove as a sort-of alias for delete...
Styles["delete-orphan"] = DeleteOrphan;
Styles["none"] = None;
}

Sure enough, "delete-orphan" is there, and it has a valid CascadeStyle
implementation:
[Serializable]
private class DeleteOrphanCascadeStyle : CascadeStyle
{
public override bool DoCascade(CascadingAction action)
{
return action == CascadingAction.Delete || action ==
CascadingAction.SaveUpdate;
}

public override bool ReallyDoCascade(CascadingAction action)
{
return action == CascadingAction.Delete;
}

public override bool HasOrphanDelete
{
get { return true; }
}
}

The question is now what to do about it. :)

[James Crowley]

It's there.

NHibernate\Engine\CascadeStyle.cs

includes "delete-orphan" . I'm in the process of adding it to Fluent
NHibernate and checking that it works as expected.. I'm guessing it
only applies to collections, as with AllDeleteOrphan.

2009/9/4 Stuart Childs <chi...@gmail.com>:

[James Crowley]

Sorry Stuart - crossed emails! Thanks for checking - 'tis good to know
I'm not going entirely mad ;)

2009/9/4 Stuart Childs <chi...@gmail.com>:

[Paul Batum]

Did anyone else LOL when they saw methods with the names "DoCascade" and "ReallyDoCascade" ? :D

[Mikael Henriksson]

Lol sorry i missed it was from the source code. Never mind my previous message!

On 9/5/09, Mikael Henriksson <mik...@zoolutions.se> wrote:
> I'd be really interested in knowing what reference you are referring
> to because I can't find it in the one i got with my download! :)

> --
> Sent from my mobile device
>

--
Sent from my mobile device

[Mikael Henriksson]

I'd be really interested in knowing what reference you are referring
to because I can't find it in the one i got with my download! :)

On 9/5/09, Paul Batum <paul....@gmail.com> wrote:

[Stuart Childs]

Just wait til you find the ReallyDoCascade().RightNow().YesImSerious() method chain. :P