Subject: Proposed Referential Integrity Requirement

From: "Slein, Judith A" <[email-masked]>
Date: Tue, 15 Sep 1998 15:41:02 -0400

A new requirement was suggested at IETF 42, that there should be a
choice about whether deleting the target of a direct reference deletes
all (direct) references.  

I do not know whether the intent was that the server should be able to
decide whether to preserve referential integrity for deletions, or
whether the intent was that a client should be able to ask that
referential integrity be preserved (or not) for a DELETE request.

In either case, I would prefer not to make a specific statement about
deletion in the requirements unless we can make similar statements about
all operations that can affect referential integrity.  

If the requirement is meant to be about server policies:  I would be
willing to make the more general statement that a server that provides
references is not required to support strong references -- that is, it
is not required to preserve referential integrity.  I think there would
be wide agreement to this requirement, particularly since we have
already agreed that the first release of the protocol specification will
not address strong references.

If the suggestion was meant to be that the client deleting the target be
able to specify whether referential integrity should be preserved,
that's probably more contentious.  At Redmond, the discussion of strong
references made it clear that there was no consensus about who should
get to decide policies about referential integrity -- the server, the
owner of the affected resource, or the client making a request. 

Judith A. Slein
Xerox Corporation
[email-masked]
(716)422-5169
800 Phillips Road 105/50C
Webster, NY 14580