[ZODB-Dev] ZODB migration to Zope 2.8

[Christian Heimes]

Dieter Maurer wrote:
 > The problem is probably larger:
 >
 >   The class information is not only coded in the object (state)
 >   itself but also in the persistent references to this object.
 >
 >   When we change the object state to use a new class (and
 >   fix the persistent reference we used for the access)
 >   all other persitent references are still wrong.
 >
 >   When we later follow such a reference, we must not
 >   try to convert the object a second time.

I don't know much about the internals of ZODB. There is a lot of hard to
understanding code in there and some crucial parts are written in C and
I'm not very well in C. I leave it to the ZODB hackers to solve the
issue. People like you, Jim or Tim are competent :)

By the way there was a discussions about the class renaming issue 2
years ago: Support for graceful ZODB Class renaming

Christian