[OAI-implementers] custom error reporting, records in which sets.

Jozef Kruger jozef@nl.adlibsoft.com
Tue, 23 Jul 2002 16:32:51 +0200


Hello Tim and others,

> > [set membership in headers]
> > So my question is, what is the precise use of this new "feature" in 
> > OAI (of reporting all sets a record occurs in)?
> 
> This allows the set hierachy to be more easily 
> mirrored/federated. In OAI 1.x the harvester has to query 
> each set to recreate the set hierachy.
Yes, which results in a minimum number of records that have to be
fetched, when you would use the setSpec in the reply to GetRecord, you
would have to fetch every single record, instead of just all the records
that appear in a set.
I don't see how this extra functionality could enhance the mirroring of
sets.
Besides, I would think that you would like to define sets without having
to change the records that go into those sets. Presuming you don't want
to do change the records, you would always have the same problem as I
do, no matter how you represent your sets.

I'd think that using the ListSets followed by a ListRecords on every set
would be the nicest and most efficient way to (for example) mirror a
site.

Also, if a set represents a meaningful relation between the records in
it, it would be logical to first query for the sets and then to get the
records from a set you're interested in. The other way around doesn't
make any sense, since you can't search for records on anything but their
Identifier.

Thanks for your reaction, awaiting more :)

Cheers,
Jozef Kruger