W3C home > Mailing lists > Public > semantic-web@w3.org > April 2008

Re: Spatial datatypes and RDF/OWL

From: Steve Harris <swh@ecs.soton.ac.uk>
Date: Mon, 14 Apr 2008 11:38:58 +0100
Cc: <semantic-web@w3.org>
Message-Id: <AAE7FBF5-7CCA-467D-ADAA-E12CE5452748@ecs.soton.ac.uk>
To: "John Goodwin" <John.Goodwin@ordnancesurvey.co.uk>

Hi John,

Sure, that's how people use geo:lat and geo:log now, eg.

   <geo:Point>
     <geo:lat>55.701</geo:lat>
     <geo:long>12.552</geo:long>
   </geo:Point>

and then query on the bNode of the Point.

It requires a fair amount of smarts in the RDF engine's index, and/or  
the FILTER function, but it's a well understood problem.

- Steve

On 14 Apr 2008, at 11:12, John Goodwin wrote:
> Hi all,
>
>
>
> Working with spatial data it would be very useful if we could extend
> RDF/OWL to include spatial datatypes. The Open Geospatial Constortium
> (OGC) provides standards for spatial datatypes and these are common  
> used
> in GML file (Geographic Markup Language - the standard for exchanging
> spatial data).
>
>
>
> Could  these spatial datatypes could be used in OWL and/or RDF in the
> same way that current XML Schema datatypes are used (in fact one of  
> the
> early version of GML was encode in RDF). It would be nice to see  
> spatial
> extension to triples stores (in an analogous way to spatial extensions
> of relational databases) that allow SPARQL queries of the form:
>
>
>
> Select ?a ?b
>
> Where
>
> {
>
>            ?a hasGeometry ?g1 .
>
>            ?b hasGeometry ?g2 .
>
>            FILTER (touches(g1,g2))
>
> }
>
>
>
> (find all a and b where a and b have touching geometries).
>
>
>
> I'm curious to know what the issues are with this from a logical point
> of view, or is it just a non-trivial engineering problem?
>
>
>
> John
>
>
> .
>
>
> This email is only intended for the person to whom it is addressed  
> and may contain confidential information. If you have received this  
> email in error, please notify the sender and delete this email which  
> must not be copied, distributed or disclosed to any other person.
>
> Unless stated otherwise, the contents of this email are personal to  
> the writer and do not represent the official view of Ordnance  
> Survey. Nor can any contract be formed on Ordnance Survey's behalf  
> via email. We reserve the right to monitor emails and attachments  
> without prior notice.
>
> Thank you for your cooperation.
>
> Ordnance Survey
> Romsey Road
> Southampton SO16 4GU
> Tel: 08456 050505
> http://www.ordnancesurvey.co.uk
>
Received on Monday, 14 April 2008 10:39:55 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 1 March 2016 07:42:03 UTC