[Project_owners] RDF question

[Axel Hecht]

Didier Ernotte wrote:
> Hi,
> 
> I have written a PHP script to extract some data from a database and
> exported them in RDF format. In my extension I am able to read this PHP
> URL into a RDFDataSource. I can also read the arc (hasArcOut), but I
> can't add a new arc (I don't want to persit the change in a file or on
> a remote server, it's only in memory). The Assert method does not seems
> to work , it look like the datasource is on a red-only mode. Do I have
> to create a separate in memory data source ? or can I change and add
> arc from a remote RDF file ?
> 
> Didier      

RDF/XML datasources are only writable if you load them from file://.

If you want to get assertions into it, you should think about 
architecture a bit, as it's usually a sign of a design bug if you want 
to assert into a remote DS. Remote DSs are shared between users, at 
least in general.
Usually, it's a good idea to seperate the user-specific parts from the 
"world" and put those into a local (in-mem or RDF/XML-in-profile) DS.

Another good rule is to never assert into a composite DS, assert into 
the DS that is right for your assertion.

Reading world, writing localized.

Axel