Hi, Thanks for the great info. This is pretty much what I was thinking as well. I've also noticed that there have been recommendations on this topic for not using generated id's or composite keys. When I think about it, I'm not sure how, with a list of customers that each has a list of orders each of which has a list of orderItems, this can be done with a single id? Maybe there is something more general that I am missing but it would seem that orderItems would require a minimum of a customer id and a order id to find the orderItem(s) for a customer. Is there something else that I might read to help me understand this? In this type of design, is it possible to let NHibernate generate all the id's and for the application not to have to worry about it?
Thanks in advance and forgive me for this being such a newbie question. Bill On Apr 13, 6:30 pm, Hudson Akridge <[email protected]> wrote: > Yup. NHibernate keeps track of all of that in the session/transaction, using > a Unit of Work pattern. How you declare your mappings has a lot to do with > whether or not something is saved/deleted/inserted properly. > If you've set up the cascades (and inverse mappings if you've got a > bi-directional) correctly, then NHibernate will do this with no problem. If > you're working on objects that you've retrieved from a persisted state using > NHibernate, then you don't even need to call a > Session.SaveOrUpdate(CustomerObject) to save the customer and all of it's > children. > > Working with the concept of dirty versus clean objects takes care of this > all for you. NHibernate will look at the objects you retrieved during your > session, and if it notices that any are dirty, it will generate the > appropriate updates. If that object contains other objects which were > removed/added/updated, the appropriate SQL will be generated for those as > well, all the way down the line recursively until everything in the in > memory object model has been checked. > > > > On Mon, Apr 13, 2009 at 3:47 PM, Bill <[email protected]> wrote: > > > Hi, > > > I have a heirarchy of classes where each contains a list of the next > > and so on. Pretty straightforward. If I have a list of Customers that > > has a list of Orders that has a list of OrderItems, if I add an Order > > and delete a OrderItem do we have to keep track of what is an Update > > verses a Insert verses a Delete or if I Save at the top level > > (Customer) will NHibernate figure out what SQL to generate? Please > > forgive me if this is a stupid question. > > > thanks! > > Bill- Hide quoted text - > > - Show quoted text - --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Fluent NHibernate" 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/fluent-nhibernate?hl=en -~----------~----~----~----~------~----~------~--~---
