[ZODB-Dev] Pluggable transactions logic

[Chris Withers]

"John D. Heintz" wrote:
> 
> I agree that putting this into the ZODB might be overkill, but I would be
> interested in it because my use of the ZODB involves objects being references
> from many places very often.  (I think that Zope's use of an object database
> "hierachtically" is really the special case, most OODBMes I believe maintain
> more graph-like data structures.)

Well, I have graph like structures in Zope ZODBs ;-)

> Here is my logic:
> My persistent object is used in by many "soft" containers.
> I want to know when (or maybe force) no more containers refer to my object.

So, you want to force your object's refcount to decrease to zero?

> I could implement this with Subject-Observer style ref counting.
> The ZODB already *has* this information.
> Wouldn't it be great to just get "where used" from the DB?

Would this solve the three indexing situations of add/modify/delete
notification?
If so, how would it work, since I lost you a bit there ;-)

> Anyway, I'm not at a point where I'm campaining for API changes or anything
> yet, but I don't think we should rule out exposing the DB garbage collection
> functionality from the ZODB API.

As always, if it helps me index stuff automatically, I'm all up for it :-)

cheers,

Chris