[ZODB-Dev] How to fix "CorruptedDataError: Error reading unknown oid. Found '' at 81036527"?

[Jim Fulton]

On Thu, Jul 14, 2011 at 3:58 PM, Hanno Schlichting <hanno at hannosch.eu> wrote:
> On Thu, Jul 14, 2011 at 9:40 PM, Jim Fulton <jim at zope.com> wrote:
>> On Thu, Jul 14, 2011 at 3:23 PM, Hanno Schlichting <hanno at hannosch.eu> wrote:
>>> At Jarn we've used that trick many times to repair broken internals in
>>> the intid/keyreference data structures.
>>
>> Do you have any theories why objects are going away for you?
>
> Not on a low-level.
>
> I know the culprit is five.intid which basically register
> zope.lifecycle event subscribers for all IPersistent objects to add
> and remove intid registrations.
>
> That code seems to get things wrong. But I've never dug into the code
> to figure out under what circumstances this happens. I very much
> believe this is wrong application code in five.intid. It does have to
> do some funky tricks with raising NotYet exceptions and handling those
> at transaction boundaries, as the intid is calculated from the p_oid.
> A new object doesn't have a p_oid until the object is added to the
> connection.
>
> So this is rather tricky code dealing with low-level assumptions. But
> I never got a reproducible case. So I've just fixed the invalid data
> whenever I hit it and ripped out five.intid from every project where
> possible. To my knowledge no such problems exist in
> zope.intid/zope.keyreference.

Is the symptom you're seeing POSKeyError?

Jim



-- 
Jim Fulton
http://www.linkedin.com/in/jimfulton