[ZODB-Dev] Non versioned objects

[Toby Dickenson]

On Wednesday 31 Jul 2002 6:15 pm, Jim Fulton wrote:

> If, in a transaction, you didn't store previous versions for some objec=
ts,
> then you couldn't undo that transaction, because, if you did, you'd
> undo to an inconsistent state. So, if, for a transaction, you didn't st=
ore
> previous versions for some objects, you might as well not store previou=
s
> versions for *all* objects.

I dont think thats true. Undo isnt the only use for historical revisions.=
 I=20
think its reasonable to want to keep a long history of certian important=20
objects for auditing purposes, even though you cant 'undo' back to those =
very=20
old revisions. For certain objects that shouldnt change much, I would lik=
e to=20
record all history since creation.


Of secondary importance, I can see a use for objects such as page hit cou=
nters=20
which keep no history but do not block undo. This just a fine-grained=20
object-level alternative to your solution:

> 2. We put the catalog data in a separate non-undoing storage, like the
>     Berkeley packless storage.