automatic DB cleanup proposal

On Tue, 9 Oct 2001, Wilfried Woeber, UniVie/ACOnet wrote:

>   Dear George,
>
> >I am worried that there may be *external* referencees to objects, and while
> >we have no 'contractual' obligation it might not be nice to do this
> >to people without some engagement but I expect most people would welcome
> >losing a path to spam.
>
>   without going into any detail of the proposal itself, I perceive the
>   fact that there are external references (allowed) _without "consent"
>   and without documentation_ a major flaw in the architecture.

Unfortunately (and unlike HTTP), there is no neat 'referer' field passed
by a WHOIS client to the WHOIS server that would allow any WHOIS Server
operator to identify the objects in remote databases with references to
local old/outdated/expired objects.

Then again, it is not the problem of a given WHOIS Server operator to
maintain referential integrity with databases outside their control unless
there is an agreement specifying that there will be referential integrity.
(ie, I don't think that it is an issue for most installations of the NCC
 database server software ;) )

> >As to automatic sweeping, I think there are problems with link counting
> >which are similar to those we've faced in discussing cross-database linkage
> >and references. Too many risks of the link count getting out of whack.
>
>   Fair enough, a very valid concern! But I think the proposal is trying
>   to describe the "user view" and the "abstract behaviour".

Actually, the RIPE database software (both v2/RIPE181 and v3/RPSL) already
have existing mechanisms to detect the existence of links (ie, cannot
'delete' an object while it is still being referenced by #X objects of
type 'Foo' etc ) to an object by objects within the same database.

So, keeping the link count up to date and correct is a simple (but
non-trivial for the coders) task that can be attached to the existing
create/modify/delete operations.  (ie, increment/decrement the link count
on all objects currently or no longer referenced by this object we're
currently creating/modifying/deleting).

> >I think you could use it as a guide to a sweep, but not as a determinant
> >without some review and other checks. Eg to trigger more exhaustive checks
> >to see if there are are references in twisty ways.
>
>   I agree.

A previous iteration of this issue in the db-wg can be seen at:

	http://www.ripe.net/ripe/mail-archives/db-wg/19990401-19990701/msg00003.html
	http://www.ripe.net/ripe/mail-archives/db-wg/19990401-19990701/msg00007.html
	http://www.ripe.net/ripe/mail-archives/db-wg/19990401-19990701/msg00008.html



-- 
                             Bruce Campbell                            RIPE
     Opinions expressed in this mail are my                             NCC
     own and are not that of my employer's.                      Operations