Hi,

We are developing a general API management tool to provide different 
APIs (unAPI, SRU, OAI-PMH...) with different record formats (MARC, MODS, 
DC...) to our databases. We now stumbled upon some confusion regarding 
XML formats. The basic question is "what is a format and how do you 
refer to it?"

I came to the conclusion that at least SRU schema identifiers are 
useless. In addition you can extract XML namespace URIs from XML 
Schemas, so all you need to identify a format is a link to its XML Schema.

I wrote a more detailed blog posting about this at
http://jakoblog.de/2011/02/24/xml-schema-vs-library-apis-oai-pmhsruunapi/

Does anyone of you relies on SRU schema identifiers when consuming SRU?
I think at least for XML-based formats we should only use the XML Schema 
as authoritative reference. Sure there are different applications of 
variants of one schema, but then it makes no sense to use global 
identifiers in addition to local names.

Jakob

-- 
Jakob Voß <[log in to unmask]>, skype: nichtich
Verbundzentrale des GBV (VZG) / Common Library Network
Platz der Goettinger Sieben 1, 37073 Göttingen, Germany
+49 (0)551 39-10242, http://www.gbv.de