I have a requirement to deliver a system with potentially extremely
high performance requirements (>10,000 database writes per second) and
so sharding seems the obvious technique to adopt.

I expect the system to have a reasonably complication domain model and
so it's reasonable to expect that parent-child relationships will be
fairly common and so it seems reasonable to me (obviously I'm happy to
guided here) that I would want to shard both the parent and the child
and therefore end up in a position where I've got a cross shard object
graph.

I can't see why this is neccesarily a bad thing.  Indeed it seems
(perhaps niavely) a sensible thing to do.  Why do you think it's bad?

N

On Jan 27, 11:14 pm, Ayende Rahien <[email protected]> wrote:
> Neil,
> I would argue that it IS bad. What is the actual scenario leading you to
> want cross shard graphs?
>
> On Thu, Jan 28, 2010 at 12:09 AM, Neil
> <[email protected]>wrote:
>
> > Hi Ayende,
>
> > You're right that the cross-shard object graph isn't supported in
> > Hibernate.   There's nothing to suggest that the concept is inherently
> > bad, it simply appears that it's just not been implemented yet.
>
> > I'm gonna try to see what work is required to get this functionality
> > working and if I get something sorted I'll let you all know and submit
> > a patch.
>
> > Cheers
>
> > Neil
>
> > On Jan 27, 7:30 pm, Ayende Rahien <[email protected]> wrote:
> > > Niel,
> > > The shards project is still in the process of porting.
> > > Cross shard object graph is, AFAIK, not supported in the Hibernate
> > version
> > > as well.
> > > One of the core concepts that we have in NHSHards is the idea of the root
> > > entity that determine the shard identity.
>
> > > On Mon, Jan 25, 2010 at 4:50 PM, Neil <
> > [email protected]>wrote:
>
> > > > I'm looking at using the Sharding stuff that NHibernate Contrib
> > > > provides but noticed a bit of functionality that seems to missing.
> > > > However it seems so fundamental to me that I wonder if there is some
> > > > obvious reason that it's not there...
>
> > > > I've been able to implement sharding for a single object but when I
> > > > added a many-to-one relationship things start going a bit "wrong".
> > > > Specifically I insert one "parent" object and three "children" with
> > > > the "children" each being located in a seperate Shard.  All goes fine
> > > > until a attempt to load the "children" when 2 of the 3 get an object
> > > > not found exception on the "parent".
>
> > > > As I understand it this all refered to as a "cross-shard object graph"
> > > > and appears to be unsupported but I don't understand why?  If it's
> > > > just time then fine I'll probably look to contribute and get this
> > > > functionality added in but is there some deep rooted reason this is a
> > > > bad idea?
>
> > > > --
> > > > You received this message because you are subscribed to the Google
> > Groups
> > > > "NHibernate Contrib - Development Group" group.
> > > > To post to this group, send email to [email protected].
> > > > To unsubscribe from this group, send email to
> > > > [email protected]<nhcdevs%[email protected]>
> > <nhcdevs%[email protected]<nhcdevs%[email protected]>
>
> > > > .
> > > > For more options, visit this group at
> > > >http://groups.google.com/group/nhcdevs?hl=en.
>
> > --
> > You received this message because you are subscribed to the Google Groups
> > "NHibernate Contrib - Development Group" group.
> > To post to this group, send email to [email protected].
> > To unsubscribe from this group, send email to
> > [email protected]<nhcdevs%[email protected]>
> > .
> > For more options, visit this group at
> >http://groups.google.com/group/nhcdevs?hl=en.

-- 
You received this message because you are subscribed to the Google Groups 
"NHibernate Contrib - Development Group" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to 
[email protected].
For more options, visit this group at 
http://groups.google.com/group/nhcdevs?hl=en.

Reply via email to