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> From: Jerome McDonough [mailto:[log in to unmask]]
> Sent: Wednesday, April 03, 2002 4:59 PM
>
> At 04:00 PM 4/3/2002 -0500, you wrote:
> > >> One of the big advantages of XML Schema is the ability to treat
> > > bits of XML in a much more modular, mix-and-match fashion than
> > > was possible using DTDs.  I'd say MODS should stick to defining
> >
> >This is a "big" myth propagated by the XML Schema community.  DTD's
> >can very easily be as modular and used in a mix-and-match fashion,
> >just like XML Schemas.  XML Schemas provide only "minor" advantages
> >over DTD's and for those "minor" advantages, if you rethink your
> >content model you don't really need them.
>
> Depends on how many different schemas you're trying to combine, and
> how much control you have over them.  If you're trying to
> combine document
> definitions from a variety of possibly not-very-cooperative
> sources (and I am),
> then I'd much rather be dealing in XML schema than having to develop
> a comprehensive DTD.

XML Schema's do provide a slight advantage in trying to combine different
schemas.  DTD's can be written in a modular fashion to provide the same
benefits, witness the modular XHTML standard, although they didn't quite
get it completely right.  What I have been proposing is DTD framework,
along with an XML schema.  You can have both, providing that you don't
use XML schema specific constructs.  XML schema brings a lot of baggage
to the table, especially for small computing devices.  If the MODS
standard includes rules for DTD authors in developing refinements, like
the modular XHTML standard did then you should not run into the problems
you are currently dealing with.  Standardizing the framework provides
interoperability.

>
> > > a single record format.  If you need to have a file containing
> > > multiple MODS records, it's easy enough to enable that using MODS
> > > as part of a more encompassing schema.
> >
> >Either you can define one DTD/Schema that incorporates the concept
> >of record sets or you can define one DTD/Schema for a single records
> >and one for a set of records.  Regardless, it would be better to
> >have it defined one way, via a standard, rather than an infinite
> >number of ways that each metadata community might implement it.  An
> >interoperable way is always preferable.
> >
> >So I respectfully disagree.
>
> I'm not sure you do, actually. :)  At least the disagreement
> part.  I don't really object to MODS defining a schema that
> enables sets of records to be contained in a single file;

My mis-impression was that you were objecting to defining _any_
record set definition.

> From: Geoff Mottram [mailto:[log in to unmask]]
> Sent: Wednesday, April 03, 2002 4:46 PM
>
> I'm in agreement that record sets are a good thing to have.
> I would prefer
> two DTDs -- one for a single record and a second one for a
> set of records.
>
> From: Jerome McDonough [mailto:[log in to unmask]]
> Sent: Wednesday, April 03, 2002 4:59 PM
>
> I just want to see it  written in a sensible manner, which is to
> say, separate schema files, with the one for the record set
> part being extremely sensible, and referencing a separate
> single-record-only MODS schema for the record type.

Agreed, the reason why I pointed out that you could define it as
one schema or as two.  So your comment that "I'm not sure you do,
actually" _is_ correct ;-)  I think that both you and Geoff, and
myself agree on this point.  I personally would not see a
definition for a single record and a definition for a record set
as cumbersome.  Actually, I see it as an advantage, especially
when doing Web Services.

> but since the most basic functionality required for recordsets is going to
> consist of a single tag (<recordset></recordset>), I'm not that worried
about
> getting a batch of records from someone else that happens to use
> <set_of_records> instead.

There are some assumptions you are making.  Defining a record set schema
may entail more than just a <recordset> tag.  For example, it probably
should also define xml:base, an id= attribute on the <recordset> tag,
possibly meta information about the collection set, etc.  If I take off
my theory hat and put on my employer's hat I see this as a _big_ problem.
Consider an organization that has 5000+ members and you will be receiving
these records from your members.  If your batch load program has to be
modified 5000+ times because each member defines it differently, it's a
_big_ problem.


Andy.