RE: APP?

["LeVan,Ralph" <levan@oclc.org>]

> From: Identifiers Working Group List
> [mailto:IDENTIFIERS-L@OCLC.ORG]
> On Behalf Of Houghton,Andrew
> Sent: Friday, November 09, 2007 10:50 AM
> To: identifiers-l
> Subject: RE: APP?
>
> Since the OASIS committee is already redefining SRU and is
> not tied down to maintain backward compatibility, then
> using an APP response would be worth while.  However,
> not being on the committee, its not clear why they
> would start with SRU as a basis and not APP.

Because there are no signs of any searching capability in APP?

> One of the downsides to SRU is there is no equivalent APP
> service document.  So I just cannot query a URL and find
> out about all the collections that an SRU server supports.

True.  That was in intentional decision when we created SRU.  We were
reacting to the overly complex Explain mechanism of Z39.50 that needed
to support the ability to describe how a client might search across
multiple databases.  That turned into a nightmare.

In SRU we decided to just describe the collections themselves.  I agree
that a simple list of the collections would be useful.  In fact, my SRU
server provides just such a list because I found it useful.  You can be
sure that it is being discussed in the OASIS group.

> The Explain request is for a specific collection and its,
> IMHO, worthless since while it tells you the names of the
> indexes, it doesn't tell you whether the index is a phrase
> or word index and which operators are supported on that
> index.  So if you are trying to write a generic SRU client
> to talk to unknown SRU servers in an SOA context, it
> just doesn't work.

I suspect you are reacting to my own implementation of SRU.  I'm sure
the Explain experts on the SRU list could tell us how to specify what
operations are supported on a particular index.

Ralph