Here's a (real) MARC record from the Oxford catalogue:

100 1  $a Dovey, Matthew J.
245 10 $a Analysis of Sergei Rachmaninoff's piano performances using
       inductive logic / $c Matthew J. Dovey
260    $c 1994
300    $a 60 p. : $b ill. ; $c 40 cm
502    $a Thesis (M.Sc.) - Oxford University, 1994
504    $a Includes bibliographic references
600 10 $a Rachmaninoff, Sergei, $d 1873-1943
650  0 $a Induction (Logic)
710 2  $a University of Oxford. $b Board of the Faculty of Mathematical
       Sciences. $t Thesis.
852    $a UkOxU $b Computing Lab $b COM Books $h THESIS MSC 1994 $7
       10318742 $p 300773595 $x 1681 $y Available $c 
971    $a com.gbr $b 950726

In MARC 9xx fields are for local use, and in Oxford we stick some record
metadata into the 971 field. So in this case I can tell you my MSc
thesis was catalogued by someone in the computing lab (com) with the
initials GBR on the 26 July 1995. 

If I asked for this record via SRW in MARC XML format I've probably get
the above information, but as 971 is a local Oxford field, only clients
customised for Oxford's practice would know the record provence.

If I asked for the record via SRW in DC format, I'd probably not get any
provenance information at all but just the bibliograph data.

If I asked for the record via SRW in REC format, I'd get precisely the
opposite i.e. just the 971 provenance data in a more standard form, but
no bibliographic details

In all cases I'm getting the same record back but different "views" of
that record in different syntaxes with more or less information from the
original record depending on the requested format.


> -----Original Message-----
> From: Z39.50 Next-Generation Initiative [mailto:[log in to unmask]] 
> On Behalf Of Mike Taylor
> Sent: Thursday, August 04, 2005 10:55 PM
> To: [log in to unmask]
> Subject: Re: rec context set schema
> > Date: Thu, 4 Aug 2005 22:26:19 +0100
> > From: Robert Sanderson <[log in to unmask]>
> >
> >>> It's not.  It's a schema with the same fields as the context set
> >>> has index names.
> >>
> >> But what _for_?  Seriously.  What kind of information could you
> >> represent with this schema?
> >
> > Record metadata? :)
> I know you've just being jokey, but there is a fairly serious point
> here.  We both know that a record of data about itself is meaningless
> -- the only purpose of the "rec" context-set, and corresponding
> elements, is to _accompany_ the conventional fields in a record, so as
> to provide information about the provenance of the data in those
> fields.  So I am truly puzzled about what this schema is for.  A
> record that uses it can _only_ say things like "This record was
> created on 2005-08-04 by Mike Taylor".
> What am I missing?
>  _/|_    
> ___________________________________________________________________
> /o ) \/  Mike Taylor  <[log in to unmask]>  
> )_v__/\  "What if everything is an illusion and nothing 
> exists?  In that
>          case, I definitely overpaid for my carpet" -- Woody Allen.
> --
> Listen to free demos of soundtrack music for film, TV and radio