On 11/9/05, David Binger <[EMAIL PROTECTED]> wrote: > > On Nov 9, 2005, at 9:21 AM, Syver Enstad wrote: > > >>> What I want to do is just update the persistent instance so that > >>> it will > >>> load from the new module/ new class after I have done a one time > >>> update > >>> of the database. > >>> > >> > >> I fear this will not work. > >> > >> For efficiency reasons, the class designator (usually a > >> module, classname tuple) is stored both in the object itself > >> and in persistent references. While you will be able > >> to modify the object's class the persistent references will > >> only change when the containers are stored into the ZODB. > > Is there something to prevent your update script from > setting _p_changed = 1 on every persistent object that contains > a reference to an instance of the moved class? > I think that if you do that and commit and pack the database, the > old module/class references will be purged. > > If you do this, the sys.modules hacking only has to happen > in the update script.
How do you find all the references? It seems like you would need to execute a transaction that iterated over every object in the storage and searched the pickle for references to the class. I can imagine the update transaction taking a really long time to run, which increases the possibility that it will get a conflict error. Maybe it's a resolvable conflict, but not using the current mechanism. Jeremy _______________________________________________ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org http://mail.zope.org/mailman/listinfo/zodb-dev
