If I will make item class persistent, then items will be saved independently of their parent. That means manual housekeeping. When order object is deleted, I will have to intercept that and manually delete all items objects. And this is only simplest hierarchy. Imagine how much manual work must be done in case or deeper hierarchies.
Maybe I do not understand how elephant work. Maybe it somehow automatically deletes all objects that are in a pset slot of the object being deleted. Is that the case? -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Alex Mizrahi Sent: Sunday, April 06, 2008 4:38 AM To: elephant-devel@common-lisp.net Subject: [elephant-devel] Re: Master-detail how to VV> Obviously class order must be persistent. But what about class VV> order-item? Should it be persistent too? it's better to make it persistent, so you can search on details. VV> Next question. How do you search orders that have say particular item? (mapcar #'order-of (get-instances-by-value 'order-item 'item item)) VV> Do you create a computed index on order class? some complex queries require computed indices, but it seems not in this case VV> Or do you make item class persistent and mark its name as indexed? if you're using objects anyway it makes sense to make everything a persistent object _______________________________________________ elephant-devel site list elephant-devel@common-lisp.net http://common-lisp.net/mailman/listinfo/elephant-devel _______________________________________________ elephant-devel site list elephant-devel@common-lisp.net http://common-lisp.net/mailman/listinfo/elephant-devel
