[Zope] Is data.fs corrupted?

[Chris McDonough]

> FWIW, I can also report this problem with ZDiscussions. In my case it
> stemmed from not properly deleting the ZDiscussion product before moving
> my Data.fs from 2.1.6 to 2.2.1 (I think). The symptom then was beeing
> unable to create ZSQL Methods (!) because of a missing
> ../Products/ZDBase/ZDiscussions.py file which I "fixed" by installing
> ZDBase again

Man that's weird.  But it's good info.  Does the current PTK include
ZDiscussions?

> I can however NOT import the ZDiscussions.zexp
> anymore because of "Duplicate Class Ids".

So it looks like a ZClass didn't get cleaned up properly when you deleted
the ZDiscussions through-the-web product.  It might mean that there's a
reference to an object in that area somewhere else in the ZODB.

It'd be interesting for someone (not me, I'm booked) to think about how to
write a tool that could detect orphaned instances and "strange" references
in the ZODB.