[OAI-implementers] sets - metadataPrefix relationship

Fri Dec 1 17:04:58 EST 2006

Irina Dijour wrote:
>> I have a question concerning sets - metadataPrefix relationship.
>> Is it permitted by the protocol to "attach" metadataPrefix to set?
>>>> For example, is the following situation is valid:
>> I define two sets A and B. All the records from my repository belong to
> both sets.
>> Set A "contains" records in marcxml. Set B "contains" records in oai_dc.
>> ListSets response contains 2 sets: A and B
>> ListMetadataFormats reponse contains 2 formats: marxml and oai_dc.
>> ListRecords request with set=A, metadataPrefix=marcxml - results in list
> of records
>> ListRecords request with set=A, metadataPrefix=oai_dc - results in error
> cannotDissemenateFormat
>> ListRecords request with set=B, metadataPrefix=marcxml - results in
> error cannotDissemenateFormat
>> ListRecords request with set=B, metadataPrefix=oai_dc - results in list
> of record
>> GetRecord request for any record in my repository both with
> metadataPrefix=marcxml and with
>> metadataPrefix=oai_dc results in the record in corresponding format.

My understanding is that you can have one set that delivers only oai_dc 
records, and another that delivers only marcxml records; but in the 
cases you give the appropriate error response would be noRecordsMatch 
rather than cannotDisseminateFormat.
Imagine a case where a set contained only one record that could be 
returned as marcxml. If your date range included that record, then 
you'd return the record; if not, you'd return noRecordsMatch. The same 
logic applies if there are no records in the set that can be returned as 
marcxml.
-- 
Gary McGath
Digital Library Software Engineer
Harvard University Library Office for Information Systems
http://hul.harvard.edu/~gary/index.html