You can read about it in the docs here: http://www.hibernate.org/hib_docs/nhibernate/1.2/reference/en/html/mapping.html#mapping-declaration-version and here: http://www.hibernate.org/hib_docs/nhibernate/1.2/reference/en/html/transactions.html#transactions-optimistic There might be other solutions for your problem, or you might not want to do this, but a nice side effect of optimistic concurrency with versioning is that nhibernate can distinct saved and unsaved entities by the version number. On Wed, Apr 1, 2009 at 2:33 PM, DannyT <[email protected]> wrote:
> Thanks for that, I've just been looking at this in the docs, could you > clarify that this means I need to add a version column to my table and a > Version property to my entity? > > 2009/4/1 Paco Wensveen <[email protected]> > >> You can use a "version" int property if you also want optimistic >> concurrency >> >> >> On 4/1/09, DannyT <[email protected]> wrote: >>> >>> We're using GUIDs as our identifier, however our entities may be created >>> on the server (which we rely on NH to sort out the IDs for) or within a >>> client application which will generate and assign the ID. >>> >>> Currently when trying to save an entity generated from the client app >>> which will have a GUID but will not already exist in the NH db I get the >>> error: >>> >>> NHibernate.StaleStateException: Unexpected row count: 0; expected: 1 >>> >>> Should NH not detect the entity doesn't already exist in the database, >>> despite the fact it has an ID and insert it? Otherwise what else should we >>> be doing to allow for this? >>> >>> Dan >>> >>> >>> >> >> >> > > > -- > http://danny-t.co.uk > > > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "nhusers" 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/nhusers?hl=en -~----------~----~----~----~------~----~------~--~---
