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> Date: Tue, 3 Jun 2003 15:32:57 +0200
> From: Theo van Veen <[log in to unmask]>
>
> I have the impression that there still is a lot of confusion. URI's
> to address metadata records are different from URI's to adress the
> digital objects that are described by these metadata records.

Yes.

> The first one is part of the metadata profile (e.g. <dc: identifier
> xsi:type=dcterms:URI>) .

No, that's the second one.  Dublin core _defines_ metadata elements
which _describe_ (and in this case point to) data.  It doesn't define
record-data elements for describing metadata.

SRW/U does, however.  It provides for locating a particular metadata
record by means of two mechanisms:

* A record's unique ID _within its SRW/U database_, to be returned as
  a part of a record using the "id" element from the Record Metadata
  Schema described at
        http://srw.o-r-g.org/schemas/rec/1.0/

* That record-ID can be forged into a URI for the record using the CQL
  query rec.id=<value>, where the "id" index is in the Record Metadata
  Index Set described at
        http://srw.o-r-g.org/indexSets/rec/1.0/

So if I find a record that I like which searching an SRU database at
        http://foo.bar.org/sru/db1
and that record includes an element "id" (from the Record Metadata
Schema) with value "12368", then I can reliably retrieve that record
later with URI
        http://foo.bar.org/sru/db1?query=rec.id=12368

> Having a special SRW parameter for recordid (as well in the response
> as in the URL request) allows a clear distinction between requesting
> records via SRW and searching via CQL, but maybe wanting that is a
> matter of taste.

The so-called "distinction" is fictitious.

 _/|_    _______________________________________________________________
/o ) \/  Mike Taylor  <[log in to unmask]>  http://www.miketaylor.org.uk
)_v__/\  "To bleed the lyric for this song, to write the rites to
         right my wrongs" -- Marillion, "Script for a Jester's Tear"

--
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