OCLC allows for a single free reclamation project that will do just this. Basically you send them your entire MARC file and they compare to what they have. They do a pretty thorough match, so even if you have records without OCLC numbers, they'll generally hit pretty well. Basically, OCLC wipes out your holdings on their end and re-sets it based on what you send them.
The assumption, of course, is that going forward you'll process deleted holdings on your own. If you generally have OCLC numbers in your MARC records, it's very simple to process deleted holdings with a text file and the Connexion client. I do it monthly as a part of my statistics-keeping workflow.
From: Code for Libraries on behalf of Stuart Spore
Sent: Wed 2/1/2012 9:51 AM
To: [log in to unmask]
Subject: Re: [CODE4LIB] OCLC control number access
Thanks for the suggestion. What I had in mind was comparing the control
numbers from our OPAC with the control numbers from OCLC so that we could
identify any discrenpencies, e..g., record delete from OPAC but holdings
not removed from OCLC.
On Wed, Feb 1, 2012 at 9:17 AM, Ed Summers <[log in to unmask]> wrote:
> On Tue, Jan 31, 2012 at 3:45 PM, Stuart Spore <[log in to unmask]> wrote:
> > If I can be forgiven a possibly naive question, is it possible to quickly
> > and freely get a list of all the OCLC control numbers associated with an
> > OCLC symbol (your own or someone else's) without resorting to any
> > (& contractual) batchload service or the like?
> If it's your own symbol I guess you could dump your OPAC as MARC and
> rifle through it with a script? If it's someone else's you could ask
> them for a dump of their opac as MARC and rifle through it. I seem to
> remember the Worldcat API had some support for giving holdings
> That probably wasn't very helpful, since it's probably not going to be
> "quick" but sometimes the obvious answer isn't very obvious.
\7c Stuart Spore
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\7c NYU Health Sciences Libraries
\7c NYU School of Medicine
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