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> What we wanted was for the metadata elements for the record to be mapped
> into the schema, not the elements of the record.  The use of a distinguished
> schema name to accomplish that distinction is bothersome.  (I'm not saying
> absolutely unconscionable.  I'll leave that to Mike. :-)

I'll leave it to Mike as well, but I'll agree when he does it :)
I didn't intend rec to be somehow semantically special as a schema. In
fact, I recall discussing with Adam, possibly not on the list, about how
to include it as a namespace in other schemas and how that could be
requested ... eg dc+rec for a simple data + metadata schema.

> I think we want a more explicit way to say that we're requesting record
> metadata elements.

Yes.

The main issue, as I see it, is the number of available metadata schemas
(1 or many).

If we limit it to one, all we need to do is include metadata and
metadataXML (cf recordData and recordXML) in the record object, using the
same rule as recordPacking.  There's no added complexity to the request,
no new diagnostics.

But one size never fits all.

So if we have multiple metadata schemas available, then we need a way to
request the one we want.  We also need a way to say that it's unknown or
not available, and what schema it actually is.

So it would end up something like:

<record>
  <metadataRecord>
    <metadataSchema>
    <metadataData> or <metadataXML>
  </metadataRecord>
  <recordData> or <recordXML>
  <recordPosition>
</record>

Plus a <metadataSchema> element in the request.  For compatability, I'd
think that if not present it would default to 'don't send me any
metadata', and present but empty would be default metadata schema.

Not overly complex and certainly better than the alternatives of no
metadata, one set metadata schema, or server's choice of metadata schema.

What's /really/ a problem is if you then want to sort based on the
metadata rather than the record.  For example, retrieving a set of records
sorted by record length or last modified time.  I don't have a good answer
for that beyond putting a new boolean typed element into the sort key
definition.

Rob


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