[OAI-implementers] Clarification on deleted records

[Alan Kent]

On Wed, Apr 10, 2002 at 02:47:46PM -0400, Hussein Suleman wrote:
> hi
> ... if deleted records are not tracked... the 
> service provider has to regularly issue GetRecord with the identifiers 
> of previously harvested records in order to confirm that each of them 
> does still exist...

I am not suggesting it today, but I can see the time when someone
may therefore want a new command to say 'are these 1,000 identifiers
still valid?'. Doing a GetRecord per identifier one by one could
be pretty slow and will unnecessarily return the record (when all
you want to know is if it exists).

I was initially thinking 'no-one would ever do GetRecord for every
record in the database - its too slow! doing ListRecords or ListIdentifiers
would always be faster', but then I realised you could always do a
GetRecord on records past a certain age. Even then though, was it
ETDCAT that had 500,000 records that came into existance one the
same day? 1/2 million GetRecord requests is not a very serious
option.

I am not proposing a new verb though. Sending 1,000 identifiers
or whatever through in a request I suspect won't be a serious option
until OAI requests are embedded in something like SOAP. POST would
work I guess, but GET???!?! (that would be one long URL!).
Periodic complete rehavesting seems the best solution with the
protocol as is.

Alan