Does schema.org support global identifiers for items?

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Philip Jägenstedt

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Jun 22, 2011, 4:23:01 AM6/22/11
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The concept is defined in
<http://www.whatwg.org/specs/web-apps/current-work/complete/microdata.html#support-global-identifiers-for-items>
and means that you can do things like

<p itemscope itemtype="http://schema.org/Person"
itemid="http://foolip.org/"><span itemprop="name">Philip</span></p>

This might seem like an academic questions, but it is what defines if
validators for schema.org should allow itemid or not. Do any of the
sponsors do anything with itemid? If not, updating the documentation
to explicitly say that it is not allowed (and ignored) would be most
welcome.

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Philip Jägenstedt

Philip Jägenstedt

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Jun 22, 2011, 4:25:18 AM6/22/11
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I should also mention that this discussion started at <http://
www.w3.org/Bugs/Public/show_bug.cgi?id=13007>, for some background.

Martin Hepp

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Jun 22, 2011, 5:26:12 AM6/22/11
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Please, do not disallow global identifiers for items!
This is key for helping search engines to connect dots distributed across large e-commerce shop sites.

--------------------------------------------------------
martin hepp
e-business & web science research group
universitaet der bundeswehr muenchen

e-mail: he...@ebusiness-unibw.org
phone: +49-(0)89-6004-4217
fax: +49-(0)89-6004-4620
www: http://www.unibw.de/ebusiness/ (group)
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skype: mfhepp
twitter: mfhepp

Philip Jägenstedt

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Jun 22, 2011, 6:44:41 AM6/22/11
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On Wed, Jun 22, 2011 at 11:26, Martin Hepp <mfh...@gmail.com> wrote:
> Please, do not disallow global identifiers for items!
> This is key for helping search engines to connect dots distributed across large e-commerce shop sites.

Only if the sponsors actually do something with it, hence the
question. If they do something with it, then I hope it's going to be
documented.

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Philip Jägenstedt

Peter Mika

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Jun 22, 2011, 6:52:42 AM6/22/11
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Hi Philip,

We plan to provide an example showing the usage of itemid, and also
examples showing the usage of microdata in the header.

Cheers,
Peter

Kingsley Idehen

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Jun 22, 2011, 6:56:53 AM6/22/11
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On 6/22/11 11:52 AM, Peter Mika wrote:
> Hi Philip,
>
> We plan to provide an example showing the usage of itemid, and also
> examples showing the usage of microdata in the header.

Even if you weren't, as Martin already explained, it shouldn't be
disallowed, removed, or undermined in anyway. Its part of the spec.

Kingsley


>
> Cheers,
> Peter
>
>
>
>
> On 6/22/11 12:44 PM, Philip J�genstedt wrote:
>> On Wed, Jun 22, 2011 at 11:26, Martin Hepp<mfh...@gmail.com> wrote:
>>> Please, do not disallow global identifiers for items!
>>> This is key for helping search engines to connect dots distributed
>>> across large e-commerce shop sites.
>> Only if the sponsors actually do something with it, hence the
>> question. If they do something with it, then I hope it's going to be
>> documented.
>>
>
>


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Regards,

Kingsley Idehen
President& CEO
OpenLink Software
Web: http://www.openlinksw.com
Weblog: http://www.openlinksw.com/blog/~kidehen
Twitter/Identi.ca: kidehen

Martin Hepp

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Jun 22, 2011, 10:03:21 AM6/22/11
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Why should that matter? Even if schema.org is driven by three sponsors, there will be many more clients consuming such data for a multitude of purposes.
It is actually already been crawled and considered by some RDF repositories.

So as Kingsley said - even if Google, Yahoo, and Bing don't need itemid, they MUST NOT discourage anybody from using itemid (if properly). Everything else would be a breach of the Microdata spec.

Best
Martin

--------------------------------------------------------

Lin Clark

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Jun 22, 2011, 10:10:18 AM6/22/11
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It would actually NOT be a breach of the microdata spec. The microdata spec makes clear that it is up to the vocab whether it supports itemid. Specifically, it says, "attribute that references a vocabulary that is defined to support global identifiers for items may also have an itemid attribute specified"

That said, I'm in BIG favor of using itemids, it is important for a lot of the use cases I focus on in my Drupal development. Thanks, Peter, for clarifying that this will be documented.

Best,
Lin

Martin Hepp

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Jun 22, 2011, 10:13:13 AM6/22/11
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Thanks Lin for the clarification!

IMO, a core Microdata keyword should not change its properties dependent on the vocabulary in use.

But that is rather a Microdata spec issue.
Martin

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=================================================================
* Project Main Page: http://purl.org/goodrelations/
* Quickstart Guide for Developers: http://bit.ly/quickstart4gr
* Vocabulary Reference: http://purl.org/goodrelations/v1
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Kingsley Idehen

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Jun 22, 2011, 10:36:58 AM6/22/11
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On 6/22/11 3:10 PM, Lin Clark wrote:
It would actually NOT be a breach of the microdata spec. The microdata spec makes clear that it is up to the vocab whether it supports itemid. Specifically, it says, " attribute that references a vocabulary that is defined to support global identifiers for items may also have an itemid attribute specified"

Yes, but vocab != data processor :-)



That said, I'm in BIG favor of using itemids, it is important for a lot of the use cases I focus on in my Drupal development. Thanks, Peter, for clarifying that this will be documented.

However we get there, it shouldn't be tampered with :-)


Kingsley
-- 

Regards,

Kingsley Idehen	      
President & CEO 
OpenLink Software     
Web: http://www.openlinksw.com

Guha

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Jun 22, 2011, 1:01:48 PM6/22/11
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We strongly encourage the use of itemids.

guha

Martin Hepp

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Jun 22, 2011, 2:20:08 PM6/22/11
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A sincere thanks for this clarification!

Kingsley Idehen

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Jun 22, 2011, 3:20:44 PM6/22/11
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On 6/22/11 6:01 PM, Guha wrote:
We strongly encourage the use of itemids.

Great!

FUD that would have grown from that now 100% neutralized!

Kingsley

Philip Jägenstedt

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Jun 23, 2011, 7:23:52 AM6/23/11
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Great, will you document this on schema.org?

Philip

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Philip Jägenstedt

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