[Zope] Zope hanging: internal ZODB error?

[Michel Pelletier]

"R. David Murray" wrote:
> 
> On Fri, 24 Mar 2000, Michel Pelletier wrote:
> > it, therefore, I cannot fix it.  The only thing I can tell you is that
> > it has to do with ZClasses that catalog themselves and that it happens
> > rarely and that updating your catalog allways fixes it.  I suspect it
> > has to do with poorly engineered ZClasses.
> 
> What would constitute a poorly engineered ZClass? 

It's just a suspicion, and as I noted in my previous mail I cant tell
you constitutes a poorly engineered ZClass because I can't reproduce the
bug.  By 'poorly engineered' I mean both the possibility that the bug is
manifest of the user createing the ZClass, _or_ that the ZClass
implementation is broken.  I did not mean to point fingers.

> I've seen this
> problem with a ZClass that is descended from just CatalogAware,
> has a few properties, and for which I've rewritten the Add and Edit
> methods to call reindex_object. 

Can you reproduce it deterministicly?

> I'm not sure how I could engineer
> this simple class better, but I don't really understand why I have
> to rewrite the Add and Edit methods to call reindex_object,

Because when you change an object, you must inform the catalog that the
object has change so it can update its indexes.

> so it could well be that there are improvements that could be made.
> 
> In my case, I did not even do an update catalog.  After adding
> a few additional objects, the error message went away on its
> own. 

This is because one of your new objects filled in the missing hole, it
may have made the problem go away, but it didn't fix it.

> (I didn't do a catalog update, because if I do that the
> meta data for the id field gets completely screwed up, so I stay
> well away from catalog update).

This has never happened to me, can you reproduce this deterministicly
also?
 
> I am running under SiteAccess, and I have a sneaking suspicion my
> problems orignate there.  I'll be moving the database to a
> dedicated server soon and will remove SiteAccess.  If I see the
> error again at that point I'll let you know.

Please do. Thanks.

-Michel