[ZODB-Dev] In-memory storage with undo ability?

[Dieter Maurer]

Rooney, Mike (ext. 324) wrote at 2007-1-15 15:49 -0500:
> ...
>    raise MultipleUndoErrors(failures.items())
>MultipleUndoErrors: Undo error 0x15e1: Undo error 0x15e1: _loadBack() failed
>
>The actual line in FileStorage.py in _txn_undo_write that is raising the exception is:
>	p, prev, v, snv, ipos = self._transactionalUndoRecord(h.oid, pos, h.tid, h.prev, h.version)
>

The ZODB can only undo changes to an object when there is no later change
to this object that should not be undone.

That's natural.

However, I expect that the ZODB contains some bug that lets
the undo fail even when there are no such object changes.

I also see occasional "invalid back pointer" warnings when
the index of a "FileStorage" is rebuild and it may be possible
that the two problems are related.



-- 
Dieter