Re: Limiting a Search by URL

So . . . should I ask the ZIG for another use attribute specifically for
URLs?  All ideas and comments are appreciated.

Chris

----- Forwarded by Chris Peterson/Amigos on 02/05/2003 11:53 AM -----
                                                                                                                                        
                      Mike Taylor                                                                                                       
                      <mike@seatbooker.n        To:       peterson@amigos.org                                                           
                      et>                       cc:       ldix@loc.gov,                                                                 
                      Sent by: Mike             Subject:  Re: Limiting a Search by URL                                                  
                      Taylor                                                                                                            
                      <mike@basingstoke.                                                                                                
                      tecc.co.uk>                                                                                                       
                                                                                                                                        
                                                                                                                                        
                      01/28/2003 09:45                                                                                                  
                      AM                                                                                                                
                                                                                                                                        
                                                                                                                                        




> Date: Mon, 27 Jan 2003 12:06:33 -0600
> From: "Chris Peterson/Amigos" <peterson@amigos.org>
>
> At first, I did think about using 1209 for this search.  I checked
> with Ray to see what he thought.  He said that 1209 was added
> specifically for searching URNs, not URLs.  Ray can probably provide
> more detail on this if you want.  But he suggested that 1032 might
> be a better choice.

Sorry to butt in to this one so late in the day, but 1032 is
absolutely NOT a suitable access point for this.  It is intended for
opaque identifiers generated by the database itself, and supplied (for
example) in the localControlNumber (1,14) element of GRS-1 record so
that the application can retrieve the same record again later.  Its
use for this purpose is explicitly described in RFC 2056 (Uniform
Resource Locators for Z39.50) which is available at
 http://lcweb.loc.gov/z3950/agency/defns/rfc2056.html

I quote from section 2 ("Some Basic Concepts") of that document:

 A special case of a Z39.50 search is a "known-item"
 search, when a client intends that a search identify a
 single, known database record, or "document" (for
 purposes of illustration, assume that a database
 record corresponds to a document), and further, the
 client knows an identifier for the document that can
 be used to effect this known-item search.  In this
 case, this identifier is often referred to as a
 document identifier, or "docid".

And from section 4 ("The Z39.50 Retrieval URL"):

 The Z39.50 Retrieval URL is intended to allow a Z39.50
 session to be used as a transparent transfer mechanism
 to retrieve a specific information object.  A Z39.50
 client uses information in the URL to formulate a
 Search Request.
 [...]
 -  The docid is placed into a type-1 query, as the
    single term, in the general format (tag 45), using
    the Bib-1 attribute set, with a Use attribute value
    of docid, and a structure attribute of URx.  The
    docid string is server-defined and completely
    opaque to the client.


And from the appendix "Examples of Z39.50 URLs":

 z39.50r://melvyl.ucop.edu/mags?elecworld.v30.n19

(in which the docId is "elecworld.v30.n19")

 _/|_  _______________________________________________________________
/o ) \/  Mike Taylor   <mike@miketaylor.org.uk>   www.miketaylor.org.uk
)_v__/\  "Christianity is not about having all the answers, but
  knowing someone who does" -- Harvey Thompson.

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Received on Wednesday, 5 February 2003 12:55:58 UTC