Am 03.09.2013 21:43, schrieb David Cuenca:

A couple of months ago there was a conversation about what to do with the identifiers that should be "owl:sameAs" [1]

It's unclear to me where "owl:sameAs" would be used... it should definitely NOT be used to point to descriptions of the same thing in other repositories.

See https://www.wikidata.org/w/index.php?title=Wikidata%3AProject_chat%2FArchive%2F2013%2F07&diff=70181630&oldid=66375829.

Then there is another discussion about using a "formatter URL" property to use any catalogue/db as an id instead of creating a property [2]

That seems fine to me.

Now there is another property proposal to implement sameAs as a property taking a url. [3]

Ick! That's just utterly wrong! I'll leave a message.

And this is all related to the recent thread in this mailing list about IRI-value or string-value for URLs.

That is a misunderstanding. That was purely about the internal representation of these values in code. It has nothing to to with whether or not the data type itself will support URI values or just "strict" URIs or URLs.

The URL data type should support any URL you can use in wikitext (there are some known issues with non-ascii domains right now, but that's a bug and being worked on).

So, in the end, what is the preferred approach?

I can't tell you what the Wikidata community currently views as the best way. Personally, i would use separate properties for different identifiers, and document how each such identifier maps to a URI/URL.

The "url" data type can be used for URLs, URIs, IRIs, etc. It's just a question of convention and of how you interpret the respective properties.

-- daniel