Rob, I understand that you propose to just return a diagnostic saying "I
cannot do this", but I should have looked in the explain record to find
out and try to find a known schema or just ignore this database.
I prefer the possibility of returning a diagnostic saying "I cannot do
this" and returning unsollicited short records (for which we have to
define a schema), so the user is informed about the existance of these
records and is even allowed to request the native XML records or perhaps
with a servers default stylesheet reference.

In terms of your "nail-example" according to your proposal the seller
would say "no we do not have number 5" and according to my proposal the
seller would  say "we do not have number 5 but we have number 6".

Theo


>>> [log in to unmask] 8/6/03 3:27:25 nm >>>
> Ofcourse we need diagnostics to let the server say "I cannot do
this"
> but I would like the server to return something useful in addition
to
> this diagnostic. The xPath is a nice example.

> Suppose I prefer title, author date as response and I want to
broadcast
> a query to several targets. I do not know what schemas they have
> available. I would like to say to the servers "give my title, author
and

Then you should look at their Zeerex files.

> date (by means of xPath) but if you cannot do that give me your
captions
> (default) and I will try to make something out of it". I assume that
a
> caption will not be 25 Mb there is no guarentee.

How do you request a 'caption' (whatever that is?)

> The only thing we have to agree upon is that in this case the server
> returns something useful in addition to the errormessage e.g. a
short
> DC(X)caption.

If I get a request for and EAD record in Dublin Core, it's still not
going
to be very short and your display script that expects just
title/author/date (or whatever) won't work, or will need to be very
lenient in what it accepts ... more work for the client as well as the
server.

That would mean you would need to check the diagnostics for /every/
transaction to see if it was just giving you fudged results, rather
than
checking them only if you need to to find out why you got no results
at
all.

It's like going into a hardware store and asking specifically for
number 5
nails, paying for them (in some business models), and then being given
number 6 nails with a sticker somewhere saying 'Sorry, don't do number
5,
but these are close'.

Rob

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