The scheme name is uri.

$0 is "repeatable for different control numbers or identifiers."

I have been arguing for an agreed convention for synthesizing identifiers for subdivided headings for years. It's trivial; if anyone interested I can repost a couple of ways of synthesizing canonical ids.

[Of course I'm not sure if subdivided headings are actually meaningful (Karen Markey's study is the only one I was able to find, but I had serious question marks about the methodology, and there is no other data available).]


On Jan 31, 2015 9:33 PM, "Young,Jeff (OR)" <[log in to unmask]> wrote:

This raises some climate change questions. Imagine we are updating the validation rules for MARC $0 in these cases:

True or false: values that start with the letters "http" should be treated as valid.

If the answer is true, here is a follow up question. Should the traditional "(XXX)YYYY" form of $0 be treated as a separate field entry or is $0 within a field repeatable? I wonder because more and more authority files don't bother registering in the traditional form.

If either form of identifier is acceptable, can they be reconciled using MARC?

What about constructed headings where at least some of the pieces can be controlled? Can $0 be used there too, without colliding with the 1st case?

One conclusion from this riddle might be that opaque identifiers are inherently evil and only transparent names (aka "strings") can be trusted in the long haul. Unique names seems be harder to come by, though. It's sad, but true.


> On Jan 31, 2015, at 8:10 PM, J. McRee Elrod <[log in to unmask]> wrote:
> Robert said:
>> * There's more future than there is past.
> That's debatable.  Doesn't it depend on what we do about climate change?
> The whole linked data effort may depend on resources not too long available.
>   __       __   J. McRee (Mac) Elrod ([log in to unmask])
>  {__  |   /     Special Libraries Cataloguing   HTTP://
>  ___} |__ \__________________________________________________________